Marine Navigation

Review by eFreeware

The most distinctive thing about Marine Navigation is that it sells itself as a chartplotter you buy once rather than rent. The app costs $19.99 up front, carries no ads, and the developer, Marco Palaferri, has been shipping it since 2012, with an update in August 2026. That combination is unusual in a category where chart subscriptions are the norm, and it is the reason this app tends to come up in conversations among people who resent paying every season for maps they feel they already own.

It is built for sailors, fishermen and other boaters who want their charts stored on the device and their tracks kept to themselves. The developer states plainly that the app does not track you, does not analyze your locations and does not sell your data. If you spend time on the water and would rather not have your favorite marks sitting on someone else's server, that pitch is the heart of the product.

The install base is modest by Play Store standards, over 10,000, and the average rating sits at 3.3 from 432 ratings. That is a mixed signal, and I would read it as a sign that this is a specialist tool with a demanding audience rather than a polished mass-market app. What follows is what the developer describes, and who I think will get value from it.

The S57 chart engine at the center

The feature the developer leads with is a proprietary S57 renderer, which is the technology that draws official Electronic Navigational Charts on the screen. The claim is that this engine, built in-house rather than licensed, brings ENC detail to a phone or tablet at a level of speed and detail once reserved for expensive dedicated systems. I would treat the performance comparison as marketing, but the underlying point matters: S57 support is what separates a serious chartplotter from a map viewer.

Alongside the official charts, the app offers a georeferencing tool that turns an image into a navigable chart. You can bring in a scanned chart, a satellite photo of a wreck, or any other image you have, and place it on the map so it lines up with real coordinates. The developer calls this the most revolutionary feature, and for a certain kind of user it probably is. Fishing clubs, harbor authorities and people with hand-annotated local charts have information that no commercial chart set contains.

The two features work together in a way that makes sense. Official ENC data gives you the authoritative picture of depths, channels and hazards, while custom maps let you layer your own knowledge on top of it. The app supports overlaying multiple maps and adjusting their transparency, so you can compare a scanned chart against satellite imagery without switching screens. That level of control is the reason someone would choose this over a simpler navigation app.

There is a caveat the developer puts in capital letters: good seamanship requires official charts, and this app is meant to be used alongside them rather than as a replacement. That is a sensible position for any electronic chart system, and it is worth taking at face value.

Tides, weather and the fishing forecast

Tidal data is handled entirely on the device using the FES2022b global model, which means you can check the tide at any point on the map without a connection. For anyone who plans a passage around a tidal gate or wants to know when a flat will have enough water, having that available offshore is more useful than a forecast that needs a signal.

The Fish Forecast, added recently, is aimed at anglers rather than pure navigators. It produces an Activity Score from solunar data combined with fishing weather and ocean conditions, and the latest update extends it with GPS-based scouting, saved spots and a map exploration mode. The idea is to help you decide when and where to go rather than just how to get there. Whether the score matches your own experience of a given stretch of water is something only time on the water will tell.

The rest of the toolset covers the basics competently: basic weather, moon phases, and GPX import and export so routes and marks can move between this app and other software. None of it is glamorous, but GPX support in particular is the kind of thing that quietly determines whether an app fits into an existing workflow or sits apart from it.

Navigation tools and chart sources

For actual navigation, the app provides routes, tracks and unlimited waypoints, along with an anchor alarm, a compass that reads true or magnetic, speed and direction readouts. These are the working parts of a chartplotter, and the anchor alarm in particular is the sort of feature that earns its keep on an overnight stop when the wind picks up and you would rather not be checking the shoreline at three in the morning.

Charts come from NOAA raster and ENC sets, ESRI satellite imagery, OpenSeaMap and bathymetric maps, among other sources. The developer also rebuilt the chart download system from scratch after user feedback, describing the result as clearer and more controllable. Downloads are how you get charts onto the device for offline use, so the quality of that process has a direct effect on how the app feels in practice.

The recent changes also add GPS-based heading fallback support, which matters on devices without a reliable compass sensor. It is a small note in a changelog, but it speaks to a developer who is still fixing the edges of the product more than a decade after launch.

What it costs and what it expects from you

Marine Navigation is a paid app at $19.99, with no advertising. It also offers in-app purchases, including an optional PRO subscription that unlocks professional-grade tools. A free Lite version exists for exploring the basics before committing. The choice is between owning the full version once or subscribing for more, and either path is treated as a matter of preference rather than necessity.

If you do subscribe, the terms are the standard ones: the subscription renews automatically unless you turn it off at least 24 hours before the current period ends, and you manage or cancel auto-renewal through your Google Play account after purchase. That is worth reading before you sign up rather than after.

The app expects you to plan ahead. Charts are downloaded for offline use, and while tides and the chart engine work on the device, you need to have the data you want before you leave a signal behind. It also expects a certain amount of care: this is a tool for use alongside official charts, and the developer is explicit that it cannot replace them and that you use it at your own risk.

The privacy position is the other part of what it asks of you, in the sense that it asks nothing. Locations are not tracked or analyzed, and saved data stays on the device. For anyone who has worried about a fishing spot appearing in someone else's database, that is the whole argument for choosing this app.

Getting the most from it on the water

The sensible approach with an app like this is to set it up on shore before you need it. Download the charts for the area you intend to cover, check that they render the way you expect, and build your first route and waypoint set while you still have a comfortable signal and a stable surface to work on. Arriving at a unfamiliar harbor and only then discovering which charts you have is not a good use of the app.

Custom maps reward preparation too. If you have a scanned chart of a local area or imagery of a mark you care about, georeferencing it in advance and saving it means the work is done when you are actually afloat. Overlaying it against an official chart at home, with transparency adjusted until both are readable, is how you catch misalignment before it matters.

For anglers, the Fish Forecast is best treated as one input among several rather than a verdict. Solunar theory and weather data can point you toward a promising window, but they do not know your water. The saved spots and map exploration in the latest update are the parts that let you build up your own picture over a season.

Finally, decide early whether the one-time purchase covers what you need or whether the PRO tools are worth a subscription. Both are legitimate paths, and the free Lite version is there to help you decide before spending anything.

An independent chartplotter for boaters who want to own their charts

Marine Navigation is a niche product with a clear identity. It is a $19.99 offline chartplotter from a single developer, built around official S57 charts, custom georeferenced maps and on-device tides, with an optional PRO subscription on top. The privacy stance is unambiguous, the toolset covers routes, tracks, waypoints, anchor alarm and GPX exchange, and the chart sources span NOAA, ESRI, OpenSeaMap and bathymetric data.

The rating of 3.3 from 432 ratings suggests it does not please everyone, and the narrow focus on offline charts and self-reliance explains part of that. Someone looking for a casual boating companion may find the setup demands more than they want to give. Someone who wants authoritative charts on their own device, with their marks kept private and no recurring charge unless they choose one, is the person this app is built for.

I would suggest starting with the free Lite version if the price or the subscription question gives you pause, then deciding whether the full purchase or the PRO path makes sense for the kind of boating you do. For sailors and fishermen who plan ahead and want their navigation data to stay theirs, it is a considered choice rather than an impulse one.

What's new in version 16.8.19

Added GPS-based heading fallback support. New Fish Forecast: Smart GPS, My Spots & Map Explore—scout bite potential worldwide using solunar + meteo/ocean data. Cleaner Waypoints UI with smart actions