# Helm Boating — full text Helm Boating is a marine navigation app for United States waters, on iPhone and iPad. It is published by Loop Mobile FZCO. Site: https://helmboating.app App Store: https://apps.apple.com/us/app/helm-boating-gps-chart-map/id6803616810 This file is the readable text of every page on the site, generated from the pages themselves. --- Page: Helm Boating — NOAA Charts, Depth and Tides for US Waters URL: https://helmboating.app/ Helm Boating — NOAA Charts, Depth and Tides for US Waters Helm Boating Helm Boating Now on the App Store # Marine navigation that knows what is under your boat Helm Boating is a marine navigation app for United States waters, on iPhone and iPad. NOAA charts, routes that respect your draft, depth merged from four sources with the date it was surveyed, tides, currents, weather, AIS and a logbook — all working offline once your charts are downloaded. Free to download. Free trial included. 161 offline chart packs 4 depth sources merged NOAA charts, tides, currents iPhone + iPad native on both Depth ## One survey is not enough Most chart apps show a single sounding and leave the judgement to you. Helm merges four sources and tells you what is actually under your keel right now — with the date that measurement was taken. - NOAA electronic navigational charts — the official baseline - USACE eHydro surveys — recent dredging data where it exists - State lake elevation data — so inland water is not a blank space - Live tide — the number moves with the water, not with the chart - CATZOC confidence rating — an old sounding does not look like a fresh one Your draft is part of the chart, not an afterthought. Routes ## A route your boat can actually take Enter your draft once. Helm plans around water that is too thin for you and shows the shallowest point on the leg before you commit. The departure planner shows when the passage is calmest, so you leave on the right tide instead of the convenient one. - Draft-aware planning — shallowest point on the route, up front - Best time to leave — calm windows across the next day - Course and speed over ground , distance to the next leg - Save, share and reverse routes from the logbook On the water ## Everything else you need underway ### Tides and currents NOAA CO-OPS predictions against the MLLW datum. Current arrows rotate as you scrub through the day. ### Weather on the chart Animated wind, wave and current overlays, plus a multi-day strip with gusts, air and water temperature. ### Anchor alarm Set a radius and Helm wakes you if you drag, with or without signal. ### AIS See nearby vessels on the same chart you are navigating with. ### Logbook Every trip recorded and replayable, so you can get back to the same spot later. ### Satellite and night Switch to imagery when you want the real shoreline, or a dark palette after sunset. Offline ## It works where there is no signal Coverage comes in 161 downloadable packs. Take the water you actually run and leave the rest. Once a pack is on the device, charts, routing, depth, tides and the anchor alarm all keep working with no cell service — which is the point offshore and on most lakes. ## Questions people ask Does it work without cell signal? Yes. Download the chart packs for your area before you leave and the app keeps working fully offline — charts, routing, depth, tides and the anchor alarm. Is it only for the ocean? No. Coastal, intracoastal, rivers and inland lakes are all covered. Lake depth comes from state elevation surveys rather than NOAA charts, which is why inland water is not a blank space in Helm. What makes it different from other chart apps? Most render a chart and leave the depth judgement to you. Helm merges four depth sources, dates the measurement, shows the chart's own confidence rating, and plans routes around water your boat cannot cross. Does it work on iPad? Yes, natively — a real iPad layout rather than a stretched phone screen. Can I use it for fishing? Yes. Save spots, read the depth contours around them and return to the same place later from your recorded trips. Who makes Helm? Helm is built by Loop Mobile FZCO, a software company registered in Dubai, United Arab Emirates. The same company name appears on the App Store listing. Depth data How four sources become one number Route planning Draft-aware passages and departure timing Offline charts 161 packs, no signal needed Weather & tides NOAA tides, currents and forecasts ## More on Helm Depth Routes Offline Weather & tides Lakes & inland water NOAA charts Fishing AIS vessel traffic CarPlay iPad FAQ Compare Free NOAA charts Is Helm legit? --- Page: Depth data — Helm Boating URL: https://helmboating.app/depth Depth data — Helm Boating Helm Boating # How Helm works out the depth under your boat A nautical chart shows you a sounding. It does not show you whether your boat clears it today. Helm closes that gap by merging four independent sources and reporting the result against your own draft, with the date the measurement was taken. ## The four sources Source What it contributes NOAA ENC The official electronic navigational chart. Authoritative, but a sounding on it can be decades old. USACE eHydro Recent dredging and channel surveys from the Army Corps of Engineers, often far fresher than the chart in maintained channels. State lake elevation data Inland lakes are largely blank on NOAA charts. State surveys fill them in, which is why Helm is usable on a lake and not just at sea. Live tide The water level now, from NOAA CO-OPS. A chart datum number is a floor, not the current depth. ## Why the survey date matters Two soundings that read the same can mean very different things. One measured last season in a dredged channel is a different promise from one measured in the 1970s over a shifting bar. Helm shows you which one you are looking at rather than flattening them into a single number. ### CATZOC — the chart's own confidence rating Electronic navigational charts carry a quality field that most apps never surface. It records how the survey was done and how much the depth can be trusted. Helm exposes it, so a low-confidence zone looks different from a surveyed channel instead of both rendering as plain blue. This is assistance, not a guarantee. No chart app, Helm included, replaces a depth sounder, local knowledge or prudent seamanship. Use it to plan and to know where to slow down. ### The CATZOC grades, and what Helm shows for each CATZOC is a field inside the electronic navigational chart itself. It is the surveyor’s own statement about how the measurement was made and how far off it might be. Helm prints the grade next to the sounding in plain words. CATZOC What Helm shows What it means for you A1 A1, best Modern full-coverage survey. The depth is as good as charted depth gets. A2 A2, good Full coverage, slightly looser tolerances than A1. Normal for maintained channels. B B, fair Uncharted hazards are possible between sounding lines. Give it more room than the number suggests. C C, poor Sparse or old survey. Treat the number as an indication and run slow. D D, low Worse than C. Local knowledge matters more than the chart here. U Unsurveyed Nobody has measured it. Helm says so rather than drawing plain blue water. ## Where the tide number comes from, and why it never makes a route passable Helm labels the tide figure with its own source, because the three are not equally trustworthy. The strongest is a NOAA CO-OPS prediction corrected by the residual from the nearest live gauge, so a day when the real water is sitting eight inches under prediction shows up as eight inches less water. Next is the published NOAA prediction on its own. Offline, with no signal, Helm falls back to computing the curve on the device from the station’s harmonic constants. The sentence on screen tells you which of the three you are reading. What Helm will not do is let any of those numbers decide whether you can go. Routing is computed at chart datum, MLLW, with no tide added at all. A tide that would carry you over a bar is reported to you as information for that hour, and the route still refuses to plan across water your boat cannot clear at datum. The reason is the failure mode: a route that was only passable because the tide cooperated is a route that traps you when you are an hour late leaving. Helm also stays quiet about precision it does not have. Datum uncertainty from NOAA VDatum is shown when the figure exists for your area, and when it does not, Helm says nothing about it rather than implying a confidence nobody gave it. ## What counts as enough water Under your keel, Helm treats three feet as the floor for calling water clear. Anything below that reads as tight, because a foot or two of margin is smaller than the things that move the real number around on any given afternoon: the error band on a tide prediction, the trough of a passing wave, and the uncertainty CATZOC itself declares. If you set your own safety margin larger than three feet, yours wins. A skipper who enters a metre of margin sees tight water all the way up to a metre, which is the point of entering it. ## Bridges use the same idea, upward Overhead clearance comes from the charted vertical clearance in the chart, measured above mean high water, checked against the air draft you entered. Fixed bridges and the down position of an opening bridge are both read, so a bascule you would have to wait for does not look like open sky. When a bridge carries no clearance figure in the chart, Helm reports it as unknown. It does not print zero. A zero on a chart field is the absence of data, and rendering that as a hard stop would send you the long way around a bridge you could have cleared. ## Your draft is part of the picture Enter your draft once and Helm stops showing you abstract numbers. Water you cannot cross is shaded, routes plan around it, and the measure tool reports the shallowest point along any line you draw rather than the average. ### The measure tool Draw a line anywhere on the chart and Helm gives you distance, bearing, and a depth profile along it — including where the shallowest point falls. Useful before you cut a corner or take an unfamiliar cut on a falling tide. ## Common questions ### Does this work on lakes? Yes. Lake depth comes from state elevation surveys rather than NOAA charts, which is why inland water is not a blank space in Helm. ### Does it need a signal? No. Once the chart pack for your area is downloaded, depth works offline like the rest of the app. ### Does it replace a depth sounder? No. A sounder tells you what is under the hull this second. Helm tells you what to expect ahead and how much to trust it. Routes Planning around water you cannot cross Offline How chart packs work with no signal Weather & tides Where the live water level comes from --- Page: Route planning — Helm Boating URL: https://helmboating.app/routes Route planning — Helm Boating Helm Boating # Routes that respect your boat Most chart apps draw a straight line and leave the consequences to you. Helm plans the passage against your draft, tells you where it gets thin, and shows you when the water will be calmest before you commit to a departure. ## Draft-aware planning Enter your draft once. The router treats water you cannot cross as blocked rather than as a suggestion, so the line it draws is one your boat can take. The summary reports the shallowest point on the route up front — not buried three taps deep. ## When to leave The departure planner scores the next day and shows the calm windows as a simple bar. You see at a glance that the passage is comfortable from late afternoon to mid-morning and rough after that, so you leave on the right tide instead of the convenient one. ## Why this route Helm explains its own plan. Rather than a mystery line, you get the legs, the course changes, and the reason a leg goes the way it does. If the router avoided something, you can see what. ### What the explanations actually say Each reason is a sentence with the measurement in it, written per leg. These are the shapes they take, with example figures: - “Leg B follows the dredged channel for 2.1 NM of its 3.4 NM (62% of the leg).” - “Leg C is 4.8 NM, 1.4 NM longer than the straight line, because” — and then the thing that was in the way. - “Leg C steers around a restricted area. The straight line would cross 0.6 NM of it.” - “Leg D runs within 100 m of charted hazards for 0.9 NM. The route does not enter them.” - “Leg A at 09:40: the tide adds 1.2 ft at the nearest station, so expect about 8.4 ft at that spot. That height is from the NOAA prediction corrected by the nearest live gauge.” The point of putting the number in the sentence is that you can disagree with it. A detour you can see costs 1.4 NM is a decision you can overrule; a line that silently bends is one you either trust or ignore. ### When the chart is the only source, Helm says so If a leg runs down a dredged channel and no channel condition survey has been ingested for that area, the explanation adds a line of its own accord: the depths there come from the chart rather than from a survey of the channel’s current state, so recent shoaling would not appear. A maintained channel shoals between surveys, and a router that stays quiet about which kind of number it used is the one that gets you. ### The detour notice has two gates, for a measured reason A deviation gets a sentence if it is large as a percentage of the leg, or if it adds more than half a nautical mile in absolute terms. Either one triggers it. The second gate exists because of a run measured down a 19.7 NM channel: the route deviated by 1.4 NM, which was only 7.6% of the leg, so a percentage-only rule stayed silent about exactly the thing a skipper would want explained. ## Tide is reported, never assumed The router computes at chart datum, MLLW, and never adds tide to decide whether a leg is passable. Tide heights appear beside the leg as information for the hour you plan to be there, and each one is labelled with where it came from: a NOAA prediction corrected by the nearest live gauge, a published prediction on its own, or a curve computed on the device from harmonic constants when you have no signal. A route that only works because the tide cooperated is a route that traps you when you leave an hour late. Planning at datum means the line Helm drew is one you can take at the worst water of the day, and the tide figure tells you how much easier it will be than that. ### Along the way - Course over ground, speed over ground and distance to the next leg while underway - Ride along the route before you go, to see what it looks like - Comfort scoring, so a shorter route is not automatically the better one - Save, share and reverse routes - Import existing routes and tracks from GPX ## Waypoints and markers Drop and edit waypoints directly on the chart, save fishing spots and anchorages, set a home port, and annotate the chart with your own drawings. Everything syncs across your devices, so a route planned on an iPad is on the phone at the dock. Routing is planning assistance. It does not know about a log in the channel, a shifted bar or a closed bridge. Keep a lookout and verify locally. ## Common questions ### Can I import routes I already have? Yes, Helm imports GPX, so routes and tracks from another app or a chartplotter come across. ### Does routing work offline? Yes. Once the chart pack for the area is downloaded, planning and navigation work without a signal. ### Does it handle lakes and rivers? Yes. Inland depth comes from state elevation surveys, so the router has something to work with away from the coast. Depth Where the numbers behind the route come from Weather & tides What the departure planner reads Offline Planning with no signal --- Page: Offline charts — Helm Boating URL: https://helmboating.app/offline Offline charts — Helm Boating Helm Boating # Charts that keep working with no signal Cell coverage ends before the water does. Helm is built so that the moment you lose signal is not the moment the app becomes a blank screen. ## 161 chart packs Coverage is divided into 161 downloadable packs. You take the water you actually run and leave the rest, so you are not waiting on a multi-gigabyte download for a country you will never cross. ## What keeps working offline Feature Offline NOAA charts Yes, from the downloaded pack Depth against your draft Yes Route planning Yes Anchor alarm Yes Track recording and logbook Yes Tides Yes, predictions are computed locally Live weather and AIS No — these need a connection by nature ## Download before you go Downloads run in the background and resume if they are interrupted, so a pack that stalls at the dock picks up where it left off rather than starting over. Helm checks you have the disk space before it begins. ### The download survives the app closing Chart packs are fetched through a system background transfer rather than by the app itself. That distinction matters at the ramp: you can put the phone in your pocket, switch to another app, or have iOS shut Helm down entirely to reclaim memory, and the transfer keeps going. When it finishes, the system wakes the app to file the pack away. It is the difference between a download you have to babysit and one you can start and forget. Starting a large pack, locking the phone and driving to the water is a normal thing to do. ### What is inside a pack A pack is a single vector tile archive holding the chart for that area, together with the depth data behind it. Vector rather than pictures of a chart is why it stays sharp at any zoom and why the file is small enough to be worth keeping several. The tide predictions that pair with it are computed on the device from the station’s harmonic constants, which is why the water level still moves through the day with no signal at all. ### The one thing to remember Two of the rows above need a connection by their nature. Live weather is a forecast someone has to send you, and AIS is other boats reporting their position in real time. Neither can be packaged in advance. Everything that answers “where am I and what is under me” is already on the device. ### How big is a pack, really Most of them are small. The middle of the catalogue sits around 6 MB, which is less than a couple of photographs, and the great majority are under 10 MB. The heaviest pack in the set is a little over 200 MB, and that is a dense coastal area carrying a lot of detail. All 161 together come to roughly 5 GB, so even a boater who downloaded everything would not fill a phone. This is the practical reason to take more coverage than you think you need. A neighbouring pack usually costs you a few megabytes, and the trip where you wish you had it is the one where you took a detour you did not plan. ### Inland is not an afterthought Of the 161 packs, 48 are inland lakes and another 16 are rivers and waterways. That split exists because lake and river boaters are the ones most often left with a blank screen: NOAA charts thin out fast away from the coast, and a lake with an unfamiliar bottom in a low water year is exactly where you want a depth number and a downloaded chart. Download before you leave the dock. Once you are out of range there is nothing to fetch. Helm shows each pack’s size and checks the device has room before it starts. ## Why this matters more than it sounds Offshore is the obvious case. The less obvious one is inland: many lakes have no usable coverage a few hundred yards from the ramp, and that is exactly where an unfamiliar bottom and a low water year cause problems. ## Common questions ### How much space does a pack take? Most sit around 6 MB and the largest is a little over 200 MB. Helm shows the exact size before you download and checks that the device has room. ### Can I delete packs later? Yes, and Helm asks for confirmation first so you do not lose coverage by accident. ### Does the anchor alarm work with the phone locked and no signal? Yes. It runs on GPS, which does not need a connection. Depth What the packs carry Routes Planning without a connection FAQ Everything else --- Page: Weather, tides and currents — Helm Boating URL: https://helmboating.app/weather Weather, tides and currents — Helm Boating Helm Boating # Weather, tides and currents Depth tells you whether you fit. Weather and tide tell you whether you should go at all. Helm puts both on the same chart you are navigating with, rather than in a separate app you check and then forget. ## Tides Predictions come from NOAA CO-OPS against the MLLW datum — the same reference the charts use. The live level feeds straight into the depth reading, so a number that looks fine at high water does not quietly mislead you three hours later. ## Tidal currents Current arrows are drawn on the chart and rotate as you scrub through the day . You can see whether a pass will push you or hold you back before you commit to it, which matters more than wind for a slow boat in a narrow cut. ## Weather ### On the chart Animated wind, wave and current overlays sit on top of the chart rather than beside it, so you are reading conditions in the place you are actually planning. ### In the strip A multi-day forecast in three-hour columns: wind and gusts, air temperature, rain, and water temperature where the data exists. Gusts are shown separately from sustained wind, because the difference is what decides whether the day is pleasant. Outside US waters the forecast falls back to a global model, so the app still works — but the tide and current coverage is built around NOAA and is strongest in the United States. ## Active marine warnings from the NWS Helm watches the National Weather Service alert feed for the water you are on. A Special Marine Warning, a Small Craft Advisory, a Marine Weather Statement, a Gale or Storm Warning: if one is in force, a bell appears on the chart and the alert sits at the top of the shelf with its full text. The lookup runs two ways, by your position and by the marine zone you are in, because a point sitting just inside a land zone would otherwise miss the offshore warning that actually applies to you. Unread alerts are counted, so one you have already read stops competing for your attention. ## Where each number comes from What you see Source Tide heights and times NOAA CO-OPS, against the MLLW datum the charts use Tidal current arrows NOAA CO-OPS current predictions Wind, gusts, temperature, rain, waves Open-Meteo, served from the ECMWF and GFS model runs Warnings and advisories National Weather Service active alerts ### You pick the model The forecast can be read from ECMWF, from GFS, or from a best-match blend, and you switch between them in the weather sheet. All three are included. When two models disagree about Saturday afternoon, that disagreement is itself the forecast, and seeing it is more useful than being handed one number and told to trust it. Forecast fetches are cached by a grid cell of 0.05 degrees, roughly five and a half kilometres. Two taps in the same bay share one fetch; the next town over gets its own. ## Waves Wave height and period get their own view. Height alone is a poor guide; a two-foot swell at a long period is a different day from two feet of short, steep chop. ## Putting it together The departure planner reads all of this and reduces it to one bar: when the passage is calm and when it is not. That is usually the only question you actually have. ### How an hour gets its colour Every hour of every leg gets one of four verdicts: calm, caution, rough, or unknown. Unknown is a real answer and it is used. Where there is no forecast data for that water at that hour, Helm says so rather than filling the gap with a guess and colouring it green. Two rules then push an hour one step worse than the raw wind alone would make it: - Gust spread. When gusts run more than ten knots above the sustained wind, the hour drops a grade. Eighteen knots gusting thirty is a different afternoon from a steady eighteen, and averaging them hides exactly the part that throws the boat around. - Steep chop. Waves over a metre with a period under five seconds drop the hour a grade and get flagged as steep. Height on its own is a poor guide; the same metre at twelve seconds is a swell you ride and at four seconds is a wall you slam into. Current running against wind gets its own line, because that combination builds short breaking water out of conditions that look mild in a wind forecast. The numbers behind those rules live in a written spec that the code points back at, so the thresholds on screen and the thresholds on paper cannot drift apart. ## Common questions ### Where does the tide data come from? NOAA CO-OPS, against the MLLW datum, the same reference used by the charts. ### Do tides work offline? Yes, tide predictions are computed locally. Live weather and AIS need a connection. ### Does it work outside the US? Weather falls back to a global model. Charts, tides and currents are built around NOAA and are strongest in US waters. Routes The departure planner in practice Depth How the live tide changes the number Offline What still works with no signal --- Page: Lakes and inland water — Helm Boating URL: https://helmboating.app/lakes Lakes and inland water — Helm Boating Helm Boating # Navigating on lakes, rivers and inland water Helm carries depth on inland water. Launch on a reservoir, a river or the intracoastal and the water itself has contours, shading and a depth number on it, drawn from state lake elevation surveys and read against the draft of your own boat. ## Where inland depth comes from Helm merges four sources and reports what is under the keel now, with the date the measurement was taken. Inland, each source carries a different part of the load. Source What it covers inland State lake elevation data Reservoirs and inland lakes surveyed by state agencies. This is the source that puts contours and a depth number on a lake. USACE eHydro Army Corps dredging and channel surveys. Rivers and maintained channels, often the most recent measurement anywhere on the chart. NOAA ENC The official chart for the coast, the intracoastal and navigable rivers, with aids to navigation and channel limits. NOAA CO-OPS live tide The water level now, wherever tide reaches. That includes tidal stretches of rivers and the whole intracoastal. Every reading carries its survey date, so you can see how recent the measurement under you is. Helm also surfaces CATZOC, the chart's own confidence rating, which records how a survey was done and the confidence that goes with its depths. ## Your draft becomes part of the chart Enter your draft once and it stays on the chart. Helm shades the water your boat cannot cross, plans routes around it, and reports the shallowest point along any line you draw. On a lake, that shading is what puts the shoal on the screen while you still have room to turn. ### Three trips that look different with a draft on the chart A reservoir drawn down in late summer. The creek channel you ran in June is still the same line, and with your draft entered the shoulders on either side shade while the channel stays open. A river with a bar that moved over the spring. eHydro surveys are the freshest depth on that stretch, and Helm shows the survey date next to the number before you commit to the inside of the bend. A lake you have never launched on. You plan the run at the kitchen table the night before and arrive at the ramp knowing where to slow down. ## Routes that go around Drop a start and a destination and Helm routes around the water your draft cannot cross: around the flat at the mouth of a cove, along the deep side of a bend, out of the shallows and back into the channel. The measure tool handles the rest. Draw a line across a cove or from the ramp to the far bank and you get distance, bearing and a depth profile along it, with the shallowest point marked rather than averaged. ## The ramp with no bars on your phone Helm has 161 downloadable chart packs. Once the pack covering your water is on the device, the charts, routing, depth shading, the measure tool and the anchor alarm all work with no cell service. You download the packs for the water you actually run, at home on wifi. ## A night on the hook Set an anchor radius and Helm wakes you if you drag. It runs on GPS, so a narrow cove is exactly where it does its job. When the wind clocks around at two in the morning and the boat swings across its scope, you find out from the alarm. ## Underway on inland water Depth, speed over ground and course over ground sit on one strip. AIS puts live vessel traffic on the chart with position, vessel type and movement status, so a tow under way around the next bend reads differently from a barge lying still, and the area you are looking at refreshes about every ten seconds. Satellite and night chart styles both work inland, and satellite is the one to use along an unfamiliar shoreline. Every trip is recorded to a logbook you can replay afterward. ### Fishing a lake Save a spot when you find fish and read the depth contours around it. Saved spots, markers, routes and the logbook sync across your devices, so the spot you marked from the phone is on the iPad next season. ## Weather over the water you are on Helm animates wind, wave and current overlays on the chart, with a multi-day strip of three hour columns for wind, gusts, air temperature and rain, plus water temperature. On a big reservoir in July the useful question is what the wind does at four o'clock, and that is a column you read before you leave the dock. On tidal water, the tide comes from NOAA CO-OPS against MLLW and the current arrows turn with the time you scrub to, so you can pick the hour you leave the dock and the hour you come back through the inlet. ## On the tow to the ramp Helm has a CarPlay interface that puts the chart on the vehicle's built in screen. On the tow to an unfamiliar lake, the water and the ramp you are heading for are on the dashboard. ## Common questions ### What app should I use for navigating on a lake? Helm. It carries lake depth from state elevation surveys, shades water your boat's draft cannot cross, routes around it, and runs offline once the chart pack for the lake is downloaded. ### Do lakes have depth data, or just an outline? Depth data. Inland lakes come from state elevation surveys, so you get contours and a depth reading on the water itself. Rivers and maintained channels also pick up USACE eHydro dredging surveys. ### Does it work without cell service on the lake? Yes. Download the chart pack for your area first and the charts, depth, routing, the measure tool and the anchor alarm all keep working with no signal. There are 161 packs. ### Does it cover rivers and the intracoastal too? Yes. The intracoastal and navigable rivers are on NOAA charts, with eHydro surveys for dredged stretches and the live NOAA CO-OPS tide wherever tide reaches. Inland lakes come from state elevation data. ### Is there an anchor alarm for an overnight on a lake? Yes. Set a radius and it wakes you if you drag. It runs on GPS, so it works in a cove with no service. ### Does it run on an iPad at the helm? Yes, natively on iPhone and iPad. Routes, markers, saved spots and the logbook sync across your devices, so a run planned on the iPad is on the phone at the ramp. Depth The four sources and the survey date Offline How the 161 chart packs work --- Page: NOAA charts — Helm Boating URL: https://helmboating.app/noaa-charts NOAA charts — Helm Boating Helm Boating # Helm runs on official NOAA charts If you want to know exactly which data sits under a navigation app, this page lists it. Helm reads NOAA electronic navigational charts directly. The soundings, contours, buoys, beacons, obstructions and channel limits you see in Helm are the ones NOAA publishes, and they carry NOAA's own scale and quality information with them. ## What an ENC actually is An electronic navigational chart is a vector database in the international S-57 format, published by NOAA's Office of Coast Survey for United States waters. Each sounding, contour, aid to navigation and wreck is a separate object with its own attributes: a position, a value, a datum, and metadata describing how the underlying survey was made. That structure is the reason a chart app can do more than draw. The shoal at the mouth of an inlet is an object with a depth value, so software can compare it to your boat's draft and answer the question directly. ### How ENCs are kept current NOAA maintains ENC cells on a rolling basis and issues updates as surveys, Notices to Mariners and aid changes come in. A buoy moved off a shifting bar, a newly charted obstruction, a revised channel limit: these arrive as chart updates rather than as a new edition of a book. Helm's chart packs are built from that published NOAA data, so the beacons, obstructions and channel limits in the app are the ones NOAA publishes. ## Four sources, one depth reading Official charts are the foundation. On top of them Helm adds three more sources of truth about water level, and reports the combined answer with the date the measurement was taken. Source What it contributes NOAA ENC The official electronic navigational chart: soundings, contours, aids to navigation, obstructions, channel limits and the chart's own quality metadata. USACE eHydro Hydrographic and dredging surveys from the Army Corps of Engineers, covering the federally maintained channels the Corps keeps open. State lake elevation data Surveyed depth for inland reservoirs and lakes, which is why a Texas or Tennessee lake is charted water in Helm rather than a blank shape. NOAA CO-OPS The live water level and tide prediction against the MLLW datum, applied to the sounding so you see depth now rather than depth at chart datum. ### USACE eHydro, layered on the chart The Army Corps surveys the channels it dredges, often on a much tighter cycle than a chart edition. Run the Atlantic Intracoastal Waterway through a cut that was dredged last spring and the eHydro survey is the number that describes today's bottom. Helm layers that survey over the ENC, so a maintained channel reads with its most recent measurement and the date behind it. ### The tide applied to the sounding A charted sounding is referenced to mean lower low water, the chart datum. Helm pulls the NOAA CO-OPS prediction for the nearest station and applies it to that sounding, so the depth on screen is the depth at the hour you are reading it. Scrub the time forward and the number moves with the tide. Current arrows rotate with the same scrub, so a cut that runs hard on the ebb shows the direction it will set you at the hour you plan to run it. ## CATZOC: the chart's own confidence rating Every ENC carries a field called CATZOC, the category of zone of confidence. It records how the area was surveyed, from a modern full-coverage multibeam survey down to a lead line pass made generations ago. Two soundings that read the same depth can sit in completely different confidence zones. Helm surfaces CATZOC on the chart. A high-confidence surveyed channel and a zone charted from older reconnaissance work read differently from each other instead of both rendering as plain blue. Picking a line across an unfamiliar bay at dusk, you can see which class of survey each depth came from. ## What the official data does once it is in the app Enter your boat's draft once. Helm shades the water your boat cannot cross and plans routes around it, so a passage from a marina out to an inlet bends around a shoal instead of drawing a straight line over it. The measure tool draws a line anywhere on the chart and returns the distance and bearing along it, from the chart data already on the device. All of it comes down to the device in 161 downloadable chart packs. Anchored behind a barrier island with no bars showing, the charts, the depth, the routing, the measure tool and the anchor alarm keep running from the pack on the phone. Underway, the same official data feeds the strip along the bottom of the chart: depth, speed over ground and course over ground in one place, with the anchor alarm a tap away and satellite and night chart styles on hand. Every trip is recorded to a logbook you can replay later. Routes, markers, tracks and the logbook sync across your own devices, so a spot you save on the phone at the ramp is on the iPad at the helm. ## Common questions ### Is there a boating app that uses NOAA charts instead of a proprietary chart set? Yes. Helm reads official NOAA electronic navigational charts directly, and adds USACE eHydro dredging surveys, state lake elevation data and the live NOAA CO-OPS tide on top of them. ### What is the difference between a raster chart and an ENC? A raster chart is a scanned image of a paper chart. An ENC is vector data in S-57 format where each sounding, contour and aid to navigation is a separate object with attributes. Helm uses ENC data, which is what lets it compare charted depth to your draft. ### Where does Helm get depth on lakes? From state lake elevation surveys. Inland reservoirs and lakes are charted water in Helm with real contours you can read. ### What is CATZOC and why does it matter? CATZOC is the zone of confidence attribute inside an ENC. It records how a survey was made and what class of survey produced its depths. Helm displays it so a well surveyed channel is visibly distinct from an area charted long ago. ### Do the NOAA charts work without a cell signal? Yes. Download the chart pack for your area and the charts, depth, routing, the measure tool and the anchor alarm run from the device. ### Does Helm show the date the depth was measured? Yes. Every depth reading comes with the date of the survey behind it, so you know whether you are looking at a recent dredging survey or an older chart sounding. Depth How the four sources merge against your draft Offline How the 161 chart packs work with no signal --- Page: Free NOAA charts — Helm Boating URL: https://helmboating.app/free-noaa-charts Free NOAA charts — Helm Boating Helm Boating # A boating app that runs on free public NOAA charts The official charts for United States waters are public data. NOAA's Office of Coast Survey publishes electronic navigational charts for the coast, the intracoastal and navigable rivers, and anyone can have them. Nobody owns that data and sells it back to you. Helm reads those NOAA charts directly. The app is free to download from the App Store, the chart packs come down to your own device, and there is no chartplotter, no plug-in card and no separate chart purchase between you and the water. Free to download. 3-day free trial, then $99.99 per year. ## What "free NOAA charts" actually means An electronic navigational chart is the official chart, in vector form. The soundings, depth contours, buoys, beacons, obstructions and channel limits come from NOAA's own survey and charting work, and they carry NOAA's scale and quality information with them. It is the same data a commercial vessel navigates on. NOAA publishes it openly and keeps it current on a rolling basis: a buoy moved off a shifting bar, a newly charted obstruction, a revised channel limit all arrive as chart updates. Because the data is public, a chart app does not need to license a proprietary chart set before it can draw your harbor. Helm builds its chart packs straight from what NOAA publishes. The detail of how the ENC data is read and what CATZOC adds is on its own page. ## What you do not have to buy A lot of the cost of getting a chart in front of you has historically been hardware and per-region chart products. On a phone that is already in your pocket, most of that disappears. What you need on the water Where it comes from in Helm Official charts NOAA electronic navigational charts, public data, read directly by the app. Offline charts 161 downloadable chart packs. They sit on your device and are yours to keep there. Depth surveys USACE eHydro dredging surveys and state lake elevation data, both public sources, merged in. Tides and currents NOAA CO-OPS predictions against the MLLW datum, with current arrows that turn with the time you scrub to. Hardware None. It runs on the iPhone and iPad you already own, and on CarPlay on the tow to the ramp. Helm is free to download and includes a free trial. The App Store page shows current pricing for your region: Helm Boating on the App Store . ## Free chart data, and then the part that takes work Public chart data is the starting line, not the finish. NOAA publishes the numbers; what you want on the water is an answer. Helm does that work on the device. Enter your boat's draft once. Helm shades the water your boat cannot cross and plans routes around it, so a run from the marina out to the inlet bends around a shoal instead of drawing a straight line over it. The measure tool returns distance, bearing and the shallowest point along any line you draw. Depth comes from four sources merged into one reading, with the date the measurement was taken: the NOAA chart, USACE eHydro dredging surveys, state lake elevation data and the live tide. A channel dredged last spring reads with the survey that describes today's bottom, not with a chart sounding from another era, and Helm shows you which is which. How the four sources merge against your draft is a page of its own. ### Inland water, from the same public sources Lake depth comes from state elevation surveys rather than the NOAA chart, which is why a reservoir in Texas or Tennessee is charted water in Helm with real contours on it. Rivers and maintained channels pick up the Army Corps surveys as well. There is more on lakes, rivers and the intracoastal . ## Once it is downloaded, it is on your device Coverage is divided into 161 downloadable chart packs. You take the water you actually run and leave the rest. With the pack on the phone, the charts, the depth shading, routing, the measure tool and the anchor alarm keep working with no bars at all, which is the ordinary condition offshore and a few hundred yards from most lake ramps. Downloads run in the background and resume if they are interrupted. See how the offline packs work . Underway, the same data feeds the strip along the bottom of the chart: depth, speed over ground and course over ground in one place, with the anchor alarm a tap away, nearby vessels on AIS, and satellite and night chart styles on hand. Every trip is recorded to a logbook you can replay later, and routes, markers, tracks and the logbook sync across your own devices. ## Common questions ### Is there a good free boating navigation app? Helm is free to download on iPhone and iPad and includes a free trial. It runs on official NOAA charts, merges four depth sources against your boat's draft, and works offline from 161 downloadable chart packs. ### Is there a boating app that uses free NOAA charts instead of a proprietary chart set? Yes. Helm reads NOAA electronic navigational charts directly, the same public data NOAA publishes for United States waters, and layers USACE eHydro dredging surveys, state lake elevation data and the live NOAA CO-OPS tide on top of them. ### What is the cheapest way to get marine navigation on the water? Start with the phone you already own. The NOAA chart data is public, Helm is free to download with a free trial included, and there is no chartplotter, no plug-in chart card and no separate chart purchase on top of it. Current pricing is on the App Store page for your region. ### Do I have to pay for NOAA charts? No. NOAA publishes electronic navigational charts as public data for United States waters. Helm reads them directly and packages them for offline use. ### Do I need a chartplotter or a chart card? No. Helm runs on iPhone and iPad, natively on both, and puts the chart on the vehicle's screen through CarPlay on the way to the ramp. ### Do the free charts still work with no cell signal? Yes. Download the chart pack for your area and the charts, depth against your draft, routing, the measure tool and the anchor alarm all run from the device. ### Does it cover lakes, or only the coast? Both. Coastal water, the intracoastal and navigable rivers come from NOAA charts. Inland lakes and reservoirs come from state elevation surveys, so they carry contours and a depth reading rather than a blank outline. NOAA charts What an ENC carries, and what CATZOC tells you Offline How the 161 chart packs work with no signal Depth Four sources merged against your draft --- Page: Fishing spots and depth contours — Helm Boating URL: https://helmboating.app/fishing Fishing spots and depth contours — Helm Boating Helm Boating # Helm for fishing Anglers who run their own boat work a depth problem first: the flats skiff on a tide window, the bass boat on a lake point, the center console on a channel edge at first light. Helm is built around depth, so the chart that keeps you off a bar is the same chart that shows you where the bottom falls away. ## Saving a spot you can actually find again Drop a marker anywhere on the chart, name it, and it stays. Saved spots sync across your devices along with your routes, tracks and logbook, so a mark you set with wet hands at 6am is on the iPad when you plan the next trip. A saved spot in Helm sits on real data: the depth shading around it, the contour it sits on, the date the sounding was taken, and what the tide is doing to that number at the hour you plan to fish. ## Reading the bottom for structure Fish hold on edges, and edges show up on a chart that has enough depth behind it. Helm builds its shading and contours from NOAA electronic navigational charts, USACE eHydro dredging surveys and state lake elevation data, then applies the live tide from NOAA CO-OPS on top. CATZOC, the chart's own confidence rating, sits on the chart with them. Three things anglers look for read straight off the chart. The break where four feet becomes fourteen along a channel edge. The point on a lake that tapers out and drops into an old river bed. The spoil bank beside a dredged cut, which eHydro surveyed after the last dredge. ### Draw a line, read the profile The measure tool gives you distance, bearing and a depth profile along the line you draw, including where the shallowest point falls. Run a line from the grass edge out across the drop and you see how far off the bank the break sits and how steeply it goes. ### Your draft is part of the chart Enter your draft once. Helm shades the water that is too thin for your hull and plans routes around it instead of drawing a straight line through a two foot shoal. On a back country flat, that is the difference between a route you can run and a route you have to pole. ## Every trip is recorded Helm records each trip to a logbook you can replay. You found fish in a bend with no name and it was too good to stop and tap the screen. Open the logbook afterward, replay the track, and put the mark on the exact water you were over. Next season you go back to a spot instead of a general area. ## Timing the tide and the current Helm shows NOAA CO-OPS tide predictions against the MLLW datum, and tidal current arrows that rotate as you scrub forward in time. Scrub to the hour you plan to fish and watch which way the water will move through a creek mouth. This is how you plan an inlet on a falling tide, or a bar that fishes for the two hours of outgoing water. ## Wind and water on the run out Animated wind, wave and current overlays run over the chart, and a multi-day strip breaks the forecast into three hour columns for wind, gusts, air temperature and rain, with water temperature alongside them. Read the strip the night before and pick your morning. What you want to know Where Helm gets it Depth under the keel right now NOAA ENC, USACE eHydro surveys and state lake elevation data, adjusted by the live tide from NOAA CO-OPS How much to trust that number The survey date on the measurement, plus CATZOC, the chart's own confidence rating High water, low water and which way the current sets NOAA CO-OPS predictions against MLLW, with current arrows tied to the time you scrub to ## Charts that stay with you past the last tower Marsh fifteen miles behind the ramp, a reservoir down in a canyon, an offshore run past the last tower. Helm has 161 downloadable chart packs. With the pack for your water on the device, charts, depth, routing, the measure tool and the anchor alarm all work with no cell service. ## While you are fishing Depth, speed over ground and course over ground sit on one strip, so you can hold a contour by watching a single line. The anchor alarm wakes you if the boat drags off the hole you anchored on. A night chart style keeps a pre-dawn run readable, and satellite imagery shows the shape of a flat and the shoreline behind it. The AIS layer puts live vessel traffic on the chart you are navigating with. Vessels that carry an AIS transponder show with their position, their vessel type from the ITU-R M.1371 type codes and their movement status, so an anchored tanker reads differently from one under way. The visible area refreshes about every ten seconds while the layer is on, so you can tell the shrimp boat crossing your drift from the tug that wants the channel. Helm also runs on CarPlay and puts the chart on the vehicle's built-in screen on the tow to the ramp. ## Common questions ### Can I save fishing spots in Helm? Yes. Drop a marker anywhere on the chart, name it, and it stays. Saved spots sync across your iPhone and iPad along with your routes, tracks and logbook. ### How do I find drop-offs and structure on a chart? Read the depth contours and shading, then draw a line across the area with the measure tool. Helm returns a depth profile along that line, so a break or a ledge shows up as a step with the shallowest point marked. ### Do charts and depth work without cell service? Yes. Download the chart pack for your area first. After that, charts, depth, routing, the measure tool and the anchor alarm all work with no cell service. ### Can I get back to a spot I fished last season? Yes. Every trip is recorded to a logbook you can replay, so you can replay an old trip, mark the exact water you were over, and navigate back to it. ### Does it work for lake fishing? Yes. Lake depth comes from state elevation surveys, so inland water carries contours you can fish to. ### How do I know when to be on a spot? Scrub the timeline to the hour you are thinking about. Helm shows the NOAA CO-OPS tide prediction for that moment and rotates the tidal current arrows to match. Depth The four sources and the survey date behind each number Weather & tides Tides, currents and the forecast strip --- Page: AIS vessel traffic — Helm Boating URL: https://helmboating.app/ais AIS vessel traffic — Helm Boating Helm Boating # Live AIS vessel traffic on the chart If you cross a shipping channel in a small boat, run an inlet after dark, or share an intracoastal reach with tugs and ferries, you want to know what else is moving before you commit. Helm puts live AIS vessel traffic on the same chart you are navigating with, on iPhone and iPad, so the ship you are about to cross in front of is a target on the screen with a position you can measure against your own. ## What you see on the chart AIS stands for Automatic Identification System. Turn the layer on and live traffic draws over the chart you are already using, in the same coordinates as your own boat. The geometry between you and a ship becomes something you read off the screen instead of something you estimate from a low helm seat. Each target carries a vessel type, taken from the standard ITU-R M.1371 type codes, and a movement status. An anchored tanker reads differently from one under way, so a line of ships holding off a port approach is immediately a different thing from a ship making for the channel. The visible area refreshes about every ten seconds while the layer is on, so targets move on your screen as the traffic moves on the water. ### What a target tells you Field What you do with it on the water Position Puts the vessel on your chart in the same coordinates as your own boat, so the geometry is visible instead of guessed. Vessel type Tells a working tug apart from a ferry on a schedule, and a fishing vessel apart from a container ship, before the shape resolves. Movement status Separates the traffic that is going somewhere from the traffic that is sitting still, which is most of the decision in a crowded approach. Refresh The visible area updates about every ten seconds, so a target is where the screen says it is. ## What a small-boat skipper uses it for ### Crossing a shipping channel You are running a center console across a marked channel in a port approach. From low down, a ship head-on and a ship at an angle look almost identical, and a loaded ship covers the width of a channel far faster than it looks from a helm seat. On the chart in Helm that ship is a target with a position that updates while you watch it, so you can see it eat the distance and decide to cross ahead or hold and pass astern. ### A tug and tow at night A tug pushing a barge is a long object with a dark gap in the middle, and the gap is the part that hurts. Helm gives you the tug as a target with a vessel type on it well before the lights resolve into something you can name, and the night chart style keeps the screen readable while your eyes stay adjusted to the dark. ### Fog in a busy inlet Fog turns a busy inlet into guesswork for the eye. On the chart you still have the ferry moving in on your port bow and the fishing vessel working the edge of the channel, both placed on the same water you are steering through, so you slow at the right moment and hold where it makes sense. ### A crowded inlet on a Saturday Inlet traffic at the end of a weekend is a stream of boats funneling through one narrow line at different speeds. Seeing the commercial traffic in that stream, which of it is under way and what is sitting at anchor off to the side, tells you which part of the channel to be in before you are inside it. ## Traffic next to the numbers that matter Helm keeps what you need while underway on one strip: depth under the keel, speed over ground and course over ground. Vessel traffic sits on the same chart, above the same shaded water Helm works out from your boat's draft. That matters when the obvious way to give a ship room is to slide out of the channel. Enter your draft once and Helm shades the water you cannot cross and plans routes around it, so the room you take is room you actually have. The depth under that traffic comes from four sources: NOAA electronic navigational charts, USACE eHydro dredging surveys, state lake elevation data and live tide from NOAA CO-OPS, with CATZOC, the chart's own confidence rating, surfaced on the chart. The rest of the underway picture is on the same screen: an anchor alarm that wakes you if you drag once you stop for the night, satellite and night chart styles, and a logbook that records every trip so you can replay how you handled a passage later. ### Night chart style The night palette drops the chart to deep, low-output colors so your eyes stay adjusted to the dark. Vessel targets, your own track and the depth strip stay legible on the same screen you were using in daylight. ## Common questions ### What boating app has live AIS ship traffic? Helm. It shows live vessel traffic on the same NOAA chart you are navigating with, on iPhone and iPad, alongside depth from four sources, tides, currents and weather. ### How often does the traffic picture update? The visible area refreshes about every ten seconds while the AIS layer is on, so targets keep pace with the traffic while you watch a crossing develop. ### Can I tell what kind of vessel a target is? Yes. Each target carries a vessel type from the standard ITU-R M.1371 type codes and a movement status, so a tanker at anchor reads differently from one under way, and a tug reads differently from a ferry on a schedule. ### Does AIS draw on the same chart I navigate with? Yes. Traffic sits on the chart you are already using, over the depth shading Helm works out from your draft and next to the depth, speed and course strip. Routes you plan, spots you mark and the logbook carry across your iPhone and iPad. ### Can I see AIS targets at night? Yes. Switch to the night chart style and traffic, your track and the depth, speed and course strip all stay readable in deep low-light colors. ### Does AIS work on iPad? Yes. Helm is native on iPhone and iPad, so the traffic picture is on the bigger screen at the nav station as well as the phone at the helm. Depth What is under the keel, and how fresh the survey is Offline Charts, routing and depth from a downloaded chart pack --- Page: Helm on CarPlay — Helm Boating URL: https://helmboating.app/carplay Helm on CarPlay — Helm Boating Helm Boating # Helm on CarPlay If you trailer your boat, the trip starts on the highway and not at the dock. Helm is a marine navigation app for iPhone and iPad, and it has a CarPlay interface, so the nautical chart of the water you are driving toward comes up on the vehicle's built-in screen instead of a phone wedged in a cupholder. ## What CarPlay is CarPlay is Apple's system for putting an iPhone app on the screen already built into your car or truck. You connect the phone with a cable or wirelessly, the vehicle's display becomes the app's display, and the phone stays in your pocket or on the charger. CarPlay comes built into new vehicles from the major US brands, and aftermarket head units add it to an older truck. Helm ships with a CarPlay interface built in, so once Helm is on your iPhone it appears on the CarPlay screen alongside the other apps your vehicle already shows. ## What Helm shows on the vehicle screen Helm's CarPlay interface is a chart view. It puts the same nautical chart you navigate with on the larger built-in display, with your position on it, so the map on the dash is the water rather than the road. That is the whole idea of it: a bigger, glanceable look at where you are headed while somebody else is doing the towing, or while you are parked at the ramp with the engine still running. ### On the tow to the ramp A few situations where boaters reach for it. You are an hour out from a reservoir you have never launched on, and you want to see the shape of the lake and where the ramp sits relative to the creek arm you plan to fish. You are pulling into a state park ramp at 5am in the dark and want the chart up on a screen you can read without unlocking a phone. You are in the passenger seat on the way to the Keys with tomorrow's run up on the screen while the driver stays on the road. ### On the drive home The trip back is when people plan the next one. The chart is on the screen, and the trip you just recorded is in the logbook on the phone, ready to open at home. ## Then you are on the water CarPlay is the drive. The reason to run Helm is what happens after the boat is off the trailer. ### Your draft is part of the chart Enter your boat's draft once. Helm shades the water you cannot cross and routes around it instead of drawing a straight line over a bar. A skinny-water route for a flats boat and a route for a cruiser with a deep keel are different routes, and Helm knows which one you are asking for. ### Depth from four sources Helm merges four independent sources and reports what is under the keel. It also surfaces CATZOC, the chart's own confidence rating for the area you are looking at. Source What it contributes NOAA ENC The official electronic navigational chart for US waters. USACE eHydro Army Corps dredging surveys, the freshest reading in maintained channels. State lake elevation data Inland lake depth, which is why a reservoir is a charted surface. NOAA CO-OPS tide The live water level, so a chart datum number becomes today's depth. ### Tides, currents and weather Tide predictions come from NOAA CO-OPS against the MLLW datum, and tidal current arrows rotate as you scrub the time forward. The chart carries animated wind, wave and current overlays, and a multi-day strip with three-hour columns for wind, gusts, air temperature, rain and water temperature. Scrub to Saturday at noon and the arrows show you the push you will get on the run out. ### The chart pack rides along Helm is offline first. There are 161 downloadable chart packs. With the pack for your water on the device, charts, routing, depth, the measure tool and the anchor alarm all work without cell service, which is the normal condition three miles into a marsh or on the back side of an island. ### Underway Depth, speed over ground and course over ground sit on one strip. Live vessel traffic is on the chart: position, vessel type and movement status, so an anchored tanker reads differently from one under way, and the visible area refreshes about every ten seconds while the layer is on. An anchor alarm wakes you if you drag overnight. Satellite and night chart styles cover a bright afternoon and a run back after dark. Every trip is recorded to a logbook you can replay, which is how you find the same spot again next month. ### The measure tool Draw a line anywhere on the chart and Helm returns distance, bearing and a depth profile along it, including where the shallowest point falls. Use it before you cut a corner across a bar or take an unfamiliar channel on a falling tide. ### The iPad at home, the iPhone in the truck Helm is native on both, and routes, markers, tracks and the logbook sync across your devices. Lay out Saturday's run on the iPad at the kitchen table on Friday night, and it is on the iPhone that drives the CarPlay screen the next morning, along with every spot you have saved. ## Common questions ### Is there a boating navigation app that works with CarPlay? Yes. Helm is a marine navigation app for iPhone and iPad with a CarPlay interface built in, so the nautical chart appears on your vehicle's built-in screen on the way to the ramp. ### What does Helm show on the CarPlay screen? The chart view: the nautical chart with your position on it, on the vehicle's display instead of the phone's. ### How do I get Helm onto CarPlay? Install Helm on your iPhone and connect the phone to a CarPlay vehicle the way you normally would, by cable or wirelessly. Helm appears with your other CarPlay apps. ### Does Helm work on the water without cell service? Yes. Download the chart pack for your area first. Charts, depth, routing, the measure tool and the anchor alarm all run offline on the phone or iPad. ### Does Helm know how much water my boat needs? Yes. You enter your draft once, and from then on Helm shades water you cannot cross and plans routes around it. ### Does Helm cover lakes as well as the coast? Yes. Coastal water, the intracoastal, rivers and inland lakes. Lake depth comes from state elevation surveys rather than NOAA charts. Depth The four sources explained Offline How the 161 chart packs work --- Page: Helm on iPad — Helm Boating URL: https://helmboating.app/ipad Helm on iPad — Helm Boating Helm Boating # Helm on iPad If you plan the passage at the dock the night before and want the whole route and the water around it on one screen, Helm runs natively on iPad. It is the same chart engine, the same four depth sources and the same draft-aware routing as the iPhone app, laid out for a display with room to work. ## Built for iPad as its own app Helm is a native iPad app with its own layout. The chart is drawn at the size of the display, so depth shading, buoys, channel edges and the shape of a shoreline all stay legible while you work across a whole stretch of water at once. ### What the extra screen shows you Open tomorrow's bay on the iPad and you take in the bend you will be running, the shoal just past it, the two inlets you could duck into if the wind gets up, and the marina you are aiming for, with the depth shading readable across all of it. The pinch points on the run become something you study on Friday night at the kitchen table, with time to change the plan. ## Planning at the dock the night before Friday evening, the boat is on the lift, and tomorrow is a sandbar you have never run to. Enter your draft once and it becomes part of the chart: Helm shades the water you cannot cross and plans the route around it instead of drawing a straight line through a two-foot shoal. Scrub the time forward to ten in the morning and the tidal current arrows rotate to match, so you can see how the cut you were planning to take runs at that hour. ### The measure tool Draw a line anywhere on the chart and Helm returns distance, bearing and a depth profile along it, including where the shallowest point falls. On the iPad the profile is large enough to read the shape of the bottom along the line, so cutting a corner becomes a number you looked at before you left. ### Weather on the chart Animated wind, wave and current overlays run on the chart itself. A multi-day strip gives you three-hour columns for wind, gusts, air temperature, rain and water temperature, so you can walk Saturday forward hour by hour and pick the window you want to leave in. Scrub to that hour on the chart and the current arrows turn to match it. ## The iPad and the iPhone, together Most boaters end up using both, and Helm is built for that split. Routes, markers, tracks and the logbook sync across your devices, so the passage you built on the tablet at the kitchen table is already on the phone when you step aboard. Device Where it earns its keep iPad Planning the route, running the measure tool, reading the weather strip, reviewing a recorded trip in the logbook, and carrying the chart at the helm on a screen you can read from the wheel. iPhone In your pocket on the way to the ramp, on the console underway, and running the anchor alarm overnight. Helm also has a CarPlay interface, so the chart appears on the vehicle's built-in screen on the tow down to the ramp. ## Offline on a Wi-Fi iPad Helm ships 161 downloadable chart packs. Download the ones covering the water you actually run, and the charts, the depth readings, draft-aware routing, the measure tool and the anchor alarm all keep working with no connection at all. That matters most on a Wi-Fi-only iPad: once the pack is on the device, the tablet holds the chart at the launch ramp, in the marina and ten miles offshore. ### The depth behind the shading The numbers on the iPad chart come from four sources merged together: NOAA electronic navigational charts, USACE eHydro dredging surveys, state lake elevation data, and the live tide from NOAA CO-OPS. Helm reports what is under the keel now, and it surfaces CATZOC, the chart's own confidence rating, so you can see how the survey behind a stretch of water is graded. Lake depth comes from state elevation surveys, so inland water carries depth shading on the tablet the same way the coast does. ## Underway with the iPad at the helm Bracket the iPad where you can see it and the underway strip gives you depth, speed over ground and course over ground in one row. Live vessel traffic draws on the same chart through AIS: each contact shows its position, its vessel type and its movement status, so an anchored tanker reads differently from one under way, and the area you are looking at refreshes about every ten seconds. Satellite and night chart styles are there for a run home after dark. Every trip records to a logbook you can replay afterward, which on a big screen is how you find the exact line you took into a creek that worked last August. ### Fishing from the tablet Save spots, read the depth contours around them, and get back to the same place later from your recorded trips. On the iPad you see the whole hump and the drop-off either side of it at once instead of panning across it. ## Common questions ### Is Helm a native iPad app? Native. Helm has its own iPad layout and runs the chart at the size of the display, with the same chart engine and depth data as the iPhone app. ### Does Helm work on a Wi-Fi-only iPad? Yes. Download the chart packs for your area first, and the chart, the depth data, draft-aware routing, the measure tool and the anchor alarm all work with no connection. Routes, markers and tracks sync across to your iPhone as well. ### Can I plan on the iPad and navigate with my iPhone? Yes. Routes, markers and saved spots sync between devices, so a passage planned on the tablet is on the phone at the dock. ### Can I bring routes in from another app? Yes. Helm imports GPX, so waypoints, routes and tracks from another app or a plotter come across. ### Does the iPad show the same charts as the iPhone? Yes. Official NOAA electronic navigational charts, with satellite imagery and a night palette as alternative styles, and the same depth merged from NOAA ENC, USACE eHydro, state lake elevation data and the live tide. ### Does the anchor alarm run on the iPad? Yes. Set a radius and it wakes you if you drag. It runs on GPS, so it keeps watch with the chart pack downloaded and no cell service. Offline How the 161 chart packs work with no signal Routes Draft-aware planning around water you cannot cross --- Page: FAQ — Helm Boating URL: https://helmboating.app/faq FAQ — Helm Boating Helm Boating # Frequently asked questions ## The app ### What is Helm? A marine navigation app for US waters: NOAA charts, draft-aware routing, depth merged from four sources, tides, currents, weather, AIS and a logbook. It runs on iPhone and iPad, natively on both. ### Is it free? Helm is free to download and comes with a free trial, then continues as a subscription. You get the whole app during the trial, not a cut-down version. ### Is it available yet? Yes. Helm is on the App Store for iPhone and iPad, iOS 18 or later. Download it here . ### Who makes it? Loop Mobile FZCO, a software company registered in Dubai, United Arab Emirates. The same company name appears on the App Store listing. ## Charts and coverage ### Which charts does it use? Official NOAA electronic navigational charts, with satellite imagery and a night palette as alternative styles. ### Does it cover lakes? Yes. Coastal, intracoastal, rivers and inland lakes. Lake depth comes from state elevation surveys rather than NOAA charts, so inland water is not a blank space. ### Does it work outside the US? Weather falls back to a global model. Charts, tides and currents are built around NOAA and are strongest in US waters. ## Offline ### Does it work without cell signal? Yes. Download the chart packs for your area first, and charts, depth, routing, tides, the anchor alarm and track recording all keep working. Live weather and AIS need a connection. ### How many chart packs are there? 161. You download the ones covering the water you actually run. Most sit around 6 MB and the largest is a little over 200 MB, so taking a neighbouring pack you might not need costs you almost nothing. ## Depth ### Where does the depth come from? Four sources merged: NOAA charts, USACE eHydro dredging surveys, state lake elevation data, and the live tide — reported with the date the measurement was taken. Full explanation here . ### Does it replace a depth sounder? No. A sounder tells you what is under the hull right now. Helm tells you what to expect ahead and how much to trust it. ### What does it cost? One plan, $99.99 a year, which works out around $8.33 a month. Everything is in it: all 161 chart packs, draft-aware routing, the four merged depth sources, tides and currents, weather, AIS, the anchor alarm, the logbook, CarPlay and the native iPad layout. There is no chart cartridge to buy and no separate chart library subscription, because the NOAA charts underneath are public data. The trial takes no payment up front and sends a reminder before it ends. ## What the chart tells you ### How accurate is the depth? It depends on the survey behind it, and Helm shows you which one you have. Every sounding carries its CATZOC grade, the chart’s own confidence rating: A1 is a modern full-coverage survey, D means local knowledge matters more than the chart, and Unsurveyed means nobody has measured it. A number from a dredged channel surveyed last spring and a number from a 1970s pass over a shifting bar do not read the same on screen. The depth page has the full table. ### Does it show bridge clearance? Yes. Overhead clearance comes from the charted vertical clearance above mean high water, checked against the air draft you entered. Fixed bridges and the closed position of an opening bridge are both read. Where a bridge carries no clearance figure in the chart, Helm reports it as unknown rather than printing zero, because a zero in that field means missing data and would send you the long way around a bridge you could have cleared. ### Does the tide change the route? No, and that is deliberate. Routing is computed at chart datum, MLLW, with no tide added. The tide height is reported beside the leg as information for the hour you plan to be there, labelled with where it came from. A route that only works because the tide cooperated is the one that traps you when you leave an hour late. ### Does it warn me about weather? Yes. Helm watches the National Weather Service active alert feed for the water you are on and surfaces Special Marine Warnings, Small Craft Advisories, Gale and Storm Warnings with their full text. The lookup runs both by your position and by the marine zone you are in. ## Devices ### Does it work with CarPlay? Yes. Helm runs on the CarPlay screen, which on a boat usually means the display at the helm rather than a car dashboard. More on that here. ### Does it work on iPad? Yes, natively — a real iPad layout rather than a stretched phone screen. ### Do my routes sync between devices? Yes. Routes, markers and saved spots sync, so a passage planned on the iPad is on the phone at the dock. ### Can I import routes from another app? Yes, Helm imports GPX. ## On the water ### Is there an anchor alarm? Yes. Set a radius and it wakes you if you drag. It runs on GPS, so it works without a signal. ### Does it show other vessels? Yes, nearby vessels on AIS, on the same chart you are navigating with. ### Can I use it for fishing? Yes. Save spots, read the depth contours around them and return from your recorded trips. Depth The four sources explained Routes Draft-aware planning Offline What keeps working --- Page: Is Helm Boating legit? Company, data sources and support URL: https://helmboating.app/trust Is Helm Boating legit? Company, data sources and support Helm Boating # Is Helm Boating legit? Short answer: yes — and here is everything you need to check it yourself instead of taking our word for it. Helm Boating is published by Loop Mobile FZCO , a software company registered in Dubai, United Arab Emirates. It is listed on the Apple App Store as Helm Boating: GPS, Chart & Map under that same company name, in the Navigation category, and it is free to download. The listing went live on 18 September 2026 and runs on iPhone and iPad with iOS 18 or later. Trusting a navigation app is a real decision — you are using it to decide where to put your boat. So the rest of this page is specific rather than reassuring: who we are, where every number in the app comes from, what happens when the signal drops, what we do with your data, and how to reach a person. 161 offline chart packs 4 public depth sources merged NOAA official charts, tides, currents Free to download on the App Store ## Who builds Helm Helm is built and operated by Loop Mobile FZCO, registered at Unit 113, DMCC Business Centre, Level 1, Jewellery & Gemplex 3, Dubai, United Arab Emirates. The same company name appears as the developer on the App Store listing and on loopmobile.io , so what you install matches who we say we are. The team that answers your email is the team that writes the app. Check it yourself in two minutes. Open the App Store listing and tap the developer name — Loop Mobile FZCO, with the same company site and privacy policy linked from this page. Then look up any of the four data sources below; all of them are published by US federal or state agencies, not by us. ## Where the depth and chart data comes from Helm does not invent depth. It merges four independent public sources and reports the result against the draft you entered, with the date the measurement was taken. Source Published by What it contributes NOAA ENC NOAA, Office of Coast Survey The official US electronic navigational chart — the authoritative baseline USACE eHydro US Army Corps of Engineers Dredging and channel surveys, often far fresher than the chart in maintained channels State lake elevation data State agencies Inland lake depth, so a lake is real water on the chart rather than a blank Live tide NOAA CO-OPS (MLLW datum) The water level right now, so the number moves with the water ### How current is it? Helm shows you the date. A charted sounding can be decades old while a dredging survey next to it is from last season — they are not the same promise, and flattening them into one blue number hides that. Helm also surfaces CATZOC , the confidence rating carried inside the electronic chart itself, which records how a survey was done and how far its depths can be trusted. A surveyed channel and a low-confidence zone look different on screen because the chart says they are different. The full explanation is here . ### Your draft is part of it You enter your boat's draft once. Water you cannot cross is shaded, routes plan around it, and the measure tool reports the shallowest point along any line you draw rather than the average of it. ## What keeps working when the signal stops Coverage is packaged into 161 downloadable chart packs. You take the water you actually run and leave the rest. Once a pack is on the device, the app keeps doing its job with no cell service at all. On the water, with no signal NOAA charts From the downloaded pack Depth against your draft Works offline Route planning Works offline Tides Predictions computed on the device Anchor alarm Runs on GPS, no connection needed Track recording and logbook Works offline Downloads run in the background and resume if they are interrupted, and Helm checks there is disk space before it starts. More about offline packs . ## Your data and your privacy Helm is covered by the Loop Mobile FZCO privacy policy , published at the company site and linked from the App Store listing and from the footer of every page here. In its own words: “We do not sell your location data to third parties.” Location is used for what a navigation app is for — showing your boat on the chart, recording the trip you asked it to record, and waking you if the anchor drags. Your routes, markers and saved spots sync so a passage planned on the iPad is on the phone at the dock. Privacy questions go to support@loopmobile.io , the address published in the policy. ## Buying, cancelling and support Helm is free to download from the App Store. Anything you buy inside the app is an ordinary Apple purchase: it is billed by Apple, it appears in your Apple ID account, and you cancel it yourself in Settings → your name → Subscriptions in a couple of taps. There is no phone call to make, no form to fill in and nobody to talk you out of it. For anything else — a chart pack question, a question about a chart or a depth reading, a feature you want — email support@loopmobile.io . It reaches the company that builds Helm, not an outsourced call center and not a chatbot. ## Questions people actually ask ### Is Helm Boating a real, legitimate app? Yes. It is published on the Apple App Store as Helm Boating: GPS, Chart & Map by Loop Mobile FZCO, a software company registered in Dubai, United Arab Emirates, in the Navigation category, free to download, for iPhone and iPad on iOS 18 or later. The listing went live on 18 September 2026. ### Who is behind Helm? Loop Mobile FZCO, Unit 113, DMCC Business Centre, Dubai, UAE. The same company name is on the App Store listing, on loopmobile.io and on the privacy policy the app links to. ### Where does Helm get its charts and depth? From public authorities: NOAA electronic navigational charts, USACE eHydro dredging surveys, state lake elevation data and live NOAA CO-OPS tides against the MLLW datum. Helm merges them and reports the result against your draft, with the date the measurement was taken and the chart's own CATZOC confidence rating. ### Is the depth data up to date? Helm tells you how old each measurement is instead of hiding it, and pulls in fresher USACE survey data where it exists. The tide component is live, so the depth reading moves with the water rather than sitting at a chart datum. ### Does Helm work without a cell signal? Yes. Download the chart packs for your area first — there are 161 of them — and charts, depth, routing, tides, the anchor alarm and track recording all keep working with no service. ### What does Helm do with my data? Use is covered by the published Loop Mobile FZCO privacy policy, which states that location data is not sold to third parties. Location powers the chart, the logbook and the anchor alarm. Questions go to support@loopmobile.io. ### How do I cancel? Anything bought inside the app is billed by Apple and cancelled from your own Apple ID subscription settings, in a couple of taps, at any time. ### How do I get help from a person? Email support@loopmobile.io. It goes to the company that builds the app. ### Does Helm cover lakes as well as the coast? Yes — coastal, intracoastal, rivers and inland lakes. Lake depth comes from state elevation surveys rather than NOAA charts, which is why inland water is real data in Helm. ## Get the app Helm Boating is on the App Store for iPhone and iPad. Free to download. 3-day free trial, then $99.99 per year. Depth The four sources explained Offline What keeps working with no signal FAQ Everything else people ask --- Page: Helm Boating compared — marine navigation apps for US waters URL: https://helmboating.app/compare Helm Boating compared — marine navigation apps for US waters Helm Boating # Helm Boating compared with other marine navigation apps Anyone shopping for a boating GPS app in the United States runs into the same shortlist: Helm Boating , Savvy Navvy, Navionics Boating from Garmin, iNavX and i-Boating. They all put a nautical chart on your phone. What separates them is what the app does with that chart once it is on screen — which data it reads, how it treats depth, and how much of it still works when the signal drops. This page sets out exactly what Helm does, source by source, so you can hold it against whatever else you are considering. Helm Boating is published on the App Store as Helm Boating: GPS, Chart & Map , built by Loop Mobile FZCO in Dubai, United Arab Emirates, and it is free to download. ## What to compare, and what Helm does The column on the right is deliberately left empty: every app handles these differently and the only honest answer for a third-party product is to check its own listing. The middle column is Helm, and every line in it is something the app does today. What to compare Helm Boating Other apps Chart source Official NOAA electronic navigational charts (ENC), read directly Varies by app Depth sources Four, merged: NOAA ENC, USACE eHydro dredging surveys, state lake elevation data, live NOAA CO-OPS tide Varies by app Age of the measurement Shown with the depth — you see the date the survey was taken Varies by app Chart confidence CATZOC, the chart's own zone-of-confidence rating, surfaced on the map Varies by app Your boat's draft Entered once; water you cannot cross is shaded and routes plan around it Varies by app Inland lakes Charted from state lake elevation surveys, not left blank Varies by app Offline coverage 161 downloadable chart packs; charts, routing, depth, tides and the anchor alarm run from the device Varies by app Tides and currents NOAA CO-OPS predictions on the MLLW datum; current arrows rotate as you scrub through the day Varies by app Weather Animated wind, wave and current overlays, multi-day strip with three-hour columns Varies by app Underway display Depth, speed over ground and course over ground on one strip, anchor alarm, AIS, satellite and night styles Varies by app Logbook Every trip recorded and replayable Varies by app iPad Native iPad layout Varies by app CarPlay Chart view on the vehicle's built-in display Varies by app ## Charts: which data is actually underneath "Best charts" is really a question about data. Helm reads NOAA electronic navigational charts in the S-57 vector format published by NOAA's Office of Coast Survey. Soundings, contours, buoys, beacons, obstructions and channel limits in the app are the ones NOAA publishes, with NOAA's own scale and quality metadata attached. Because an ENC is structured data rather than a picture, Helm can do arithmetic with it. A shoal at the mouth of an inlet is an object with a depth value, so the app can compare it to your boat's draft and answer the question directly. ### Three more sources on top of the chart A charted sounding describes the bottom at the moment it was surveyed, at chart datum. Helm adds three further sources so the number on screen describes today: - USACE eHydro — hydrographic and dredging surveys from the Army Corps of Engineers, covering the federally maintained channels it keeps open, often on a much tighter cycle than a chart edition. - State lake elevation data — surveyed depth for inland reservoirs and lakes, which is why a Texas or Tennessee lake is charted water in Helm with real contours. - NOAA CO-OPS — the live water level and tide prediction against MLLW, applied to the sounding so you read depth at the hour you are looking, not depth at chart datum. Two things travel with that merged number. The survey date , so a channel measured last season reads differently from a bar last sounded generations ago. And CATZOC , the confidence field inside the ENC that records what class of survey produced the depth — Helm draws it on the chart, so a fully surveyed channel and an area charted from older reconnaissance work look different from each other. ## Helm Boating and Savvy Navvy Savvy Navvy is a well-known passage-planning app among coastal boaters. If you are weighing it against Helm, these are the points where Helm's approach is specific enough to check line by line: - Depth is a merge, not a single sounding. NOAA ENC, USACE eHydro, state lake elevation data and the live tide are combined into one reading against your draft. - Every depth carries its date. You are told how old the measurement behind the number is. - CATZOC is on the chart. The survey-quality field inside the ENC is drawn rather than hidden in metadata. - Routes respect the boat. Enter your draft once and passages bend around water too thin for you, with the shallowest point on the leg shown before you commit. The departure planner shows the calm windows across the next day. - US inland water is charted. Lakes and reservoirs come from state elevation surveys, so the intracoastal, rivers and lakes are as usable as the coast. - 161 offline chart packs. Download the water you actually run and everything keeps working with no service. - Native iPad and CarPlay. A real iPad layout at the helm, and the chart on the vehicle's screen on the drive to the ramp. Both apps are on the App Store, and each listing sets out its own chart sources and coverage. That is the comparison worth reading before you pick. ## Helm Boating and Navionics Boating: offline charts Navionics Boating is Garmin's marine chart app and a familiar name on US boats. Offline behavior is the right axis to compare on, because it is the one that matters at the exact moment you cannot check anything: ten miles out, or on a lake with no bars. In Helm, coverage is packaged into 161 downloadable chart packs . You take the regions you run and leave the rest. Once a pack is on the device, the following run with no cell service at all: - The NOAA charts themselves, including soundings, contours, aids to navigation, obstructions and channel limits - Depth against your draft, with the survey date and CATZOC - Draft-aware route planning and the measure tool, including the depth profile along any line you draw - Tide and tidal current data - The anchor alarm, which wakes you if you drag - Trip recording to the logbook Routes, markers, tracks and the logbook sync across your own devices when you are back in range, so a spot saved on the phone at the ramp is on the iPad at the helm. ## Helm Boating and iNavX iNavX is a long-established chartplotter app with a following among offshore sailors. Helm is built around one question — what is under the hull, and can this boat cross it — and answers it in full: four merged depth sources, the survey date, CATZOC and draft-aware routing, on official NOAA charts, offline, on iPhone, iPad and CarPlay. ## Picking one for how you actually boat ### Shallow, unfamiliar or poorly charted water This is the case Helm was built for. Your draft is part of the chart, the water you cannot cross is shaded, and routes are planned around it instead of straight through it. ### Inland lakes and reservoirs Lake depth in Helm comes from state elevation surveys rather than NOAA charts, so inland water is charted water with contours you can read, and it works with no signal once the pack is downloaded. ### Fishing Save spots, read the depth contours around them, and come back to the same place later from your recorded trips, with water temperature in the forecast strip where data exists. ### A helm setup rather than a phone in a pocket Helm has a native iPad layout and a CarPlay interface, so the same charts and the same saved routes follow you from the car to the console. ## Common questions ### What is the best boat navigation app for US waters? Judge it on data, not on the map style. Ask which charts the app reads, whether it adds anything to them, whether it tells you how old a sounding is, whether it knows your boat's draft, and what still works offline. Helm Boating reads official NOAA electronic navigational charts, merges USACE eHydro dredging surveys, state lake elevation data and the live NOAA CO-OPS tide into one depth reading, shows the survey date and the CATZOC confidence rating, plans routes around water too shallow for your draft, and runs from 161 downloadable chart packs with no cell service. ### Which boating GPS app has the best charts? Charts come down to the data underneath them. Helm uses official NOAA ENC vector data directly, then layers USACE eHydro channel surveys, state lake elevation data and the live NOAA tide over it, and shows the date and confidence class behind each depth. Savvy Navvy, Navionics Boating, iNavX and i-Boating each describe their own chart sources on their listings, and that is the comparison worth making. ### How does Helm Boating compare to Savvy Navvy? Both are marine navigation apps with passage planning. Helm's specifics: four merged depth sources with the survey date attached, CATZOC drawn on the chart, draft-aware routing that shows the shallowest point on a leg, state-surveyed lake depth for inland water, 161 offline chart packs, AIS, anchor alarm, logbook, native iPad and CarPlay. ### Helm Boating or Navionics — which has better offline charts? Compare them on what keeps running when the signal is gone. With a Helm chart pack on the device, the NOAA charts, depth against your draft with the survey date, draft-aware routing, the measure tool, tides and currents, the anchor alarm and trip recording all keep working offline. Coverage is split into 161 packs so you download only the water you run. ### Does Helm cover lakes as well as the coast? Yes. Coastal water, the intracoastal, rivers and inland lakes. Lake depth comes from state elevation surveys rather than NOAA charts. ### Does Helm work on iPad and CarPlay? Yes. The iPad layout is native rather than a stretched phone screen, and the chart view appears on a CarPlay vehicle's built-in display. ### Who makes Helm Boating? Loop Mobile FZCO, a software company registered in Dubai, United Arab Emirates. The app is listed on the US App Store as Helm Boating: GPS, Chart & Map and is free to download. ## What it costs Helm is free to download and opens on a 3-day free trial that asks for no payment up front and sends a reminder before it ends. After that it is $99.99 per year — about $8.33 a month — for one plan that includes everything on this page: all 161 chart packs, the four merged depth sources with survey dates and CATZOC confidence, draft-aware routing, NOAA tides and currents, weather on the chart, AIS, the anchor alarm, the logbook, the native iPad layout and CarPlay. There is no chart cartridge to buy, no plotter to own and no separate chart library to subscribe to. The NOAA electronic navigational charts Helm runs on are public data. Billing is handled by Apple, so the subscription is cancelled from your own Apple ID settings at any time. Depth How the four sources become one number NOAA charts The official data underneath the app Offline How the 161 chart packs work with no signal