Comparison

OpenSeaMap vs WWF Nautical Chart

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

OpenSeaMap

This app provides a free, worldwide nautical chart with detailed sea information, including lights, weather data, and harbor details. It offers chartplotting, waypoint management, and offline map caching for navigation. Users can mark locations, enter coordinates, and adjust chart zoom for optimal viewing.

Highlights
  • Free worldwide sea chart
  • Chartplotting with tracking
  • Waypoint creation and export
  • Offline map caching
  • Mark and search locations
  • Adjustable chart zoom
Features
Read full description

OpenSeaMap is a worldwide Opensource-project for creating a free nautical chart. Founded in 2009 the project gained a lot of attention lately adding more and more nautical information for free. Not even lights and other nautical infos are provided, but also more and more info layers like weather data, information about harbours and so on. As an add on to the OpenStreetMap this provides all missing info for nautical activities. OpenSeaMap is part of OpenStreetMap and uses the same database. FEATURES: - Free worldwide sea chart (incl. HD chart graphics) - Search for geolocations worldwide - Chartplotting with continuous tracking - Waypoints can easily be created, edited, deleted & exported - Mark locations in the chart - Zoom chart optically to fit your preferred reading size - Enter coordinates directly to be displayed in the chart - Offline caching of up to 1 million map tiles - Cleanup of chart cache data at any time To ensure future development and support of the OpenSeaMap app we encourage you to buy the In-App-Product "PRO". This will help keeping new updates and features coming. DISCLAIMER: OpenSeaMap is part of the OpenStreetMap and uses the same database. As an experienced navigator you should NEVER rely your descisions on one source of information alone. Please keep in mind that the OpenSeaMap can not replace official sea charts on bord of your boat. Please use the OpenSeaMap app only in conjunction with official sea charts and conforming to national and international regulations. Please recognize that no depth information is provided by this product. IMPORTANT: The continued use of the GPS can significantly decrease the battery level.

About

WWF Nautical Chart

This app helps users navigate Wismar Bay and the Bay of Greifswald, highlighting sensitive areas and boating rules within Natura 2000 zones. It provides information on protected areas, fishing regulations, and bird species to promote harmonious coexistence between people and nature.

Highlights
  • Pinpoint location in Wismar Bay and Greifswald Bay
  • Shows sensitive areas and boating rules
  • Identifies protected Natura 2000 areas
  • Provides information on nature and regulations
  • Includes fishing and bird information
  • Routing function with waypoints
Features
Read full description

The app can be used to pinpoint your location in Wismar Bay and the Bay of Greifswald It also shows the particularly sensitive areas and boating rules in the voluntary agreements within the Natura 2000 areas. Users, e.g. people who are fishing, sailing, motor boating, kite-surfing, rowing, kayaking or canoeing, can see on their smartphone or tablet at any time whether they are inside or outside protected areas. It is no longer a valid excuse to say you don’t know where you are! The app is designed to help you comply with the BOATING RULES. Improved navigation on the water will reduce disturbances in the protected bays and in the breeding and resting areas of waterbirds. It is intended to help ensure that people and nature can co-exist in harmony in the species-rich coastal waters. Interesting information about NATURE is provided for individual areas and the legal regulations are also available for anyone who wants to know more. HOW THE APP WORKS Navigate through the Wismar Bay and the Bay of Greifswald using the routing function. Waypoints make it easy for you to avoid the protected areas. Click on the red and orange zoning or colour-coded protected areas to learn more about nature and special regulations. The “Nature” section contains a glossary with explanations of protected areas, regulations and institutions. In the “Fish” section you can find useful information about fishing, including a description of individual fish, fishing seasons, minimum sizes, periods closed to fishing and the Red List status of the individual species. The “Bird” section features common birds with photos and audio. Detailed maps can be downloaded under “Info” and then “Nautical charts”. FEATURES: - Waypoints can be set with the routing function. The distance and course of the selected route are automatically displayed. - Orange and red areas indicate when boating is permitted in the area or not. - If the boat crosses the boundary of a restricted protected area, a message automatically appears on the map. - Coloured areas provide information about the protected areas (including nature conservation areas and fish sanctuaries). - Minimum sizes and seasons closed for fishing: during the season when fishing is not permitted for a species, a crossed-out fishhook appears next to the fish. - Winter sanctuaries, fish and spawning sanctuaries are only shown on the map during the period closed for fishing. - Use the layer icon to show and hide the areas for boating and fishing. Have a great day out on the water! Enjoy your visit and please respect nature!

Screenshots

OpenSeaMap4 screens
WWF Nautical Chart4 screens

Verdict

The call

The clearest difference is review sentiment: WWF Nautical Chart at 100% against OpenSeaMap's 38%. WWF Nautical Chart also leads on in-app purchases (none vs 1) and iOS requirement (14.0 vs 18.6). OpenSeaMap's advantage is update cadence (every 2 months vs every 6 months). On price, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. OpenSeaMap sells 1 one-off in-app purchase. WWF Nautical Chart asks for nothing beyond the download.

UpkeepUpdate frequency

OpenSeaMap ships an update every 2 months, WWF Nautical Chart every 6 months. Both last shipped on October 12, 2026.

Scorecard5 real differences · 5 level
OpenSeaMap versus WWF Nautical Chart: the parameters behind the verdict, then further details
ParameterOpenSeaMapWWF Nautical Chart
PriceFreeFree
Rating1.0 (1 ratings) — better—
Positive reviews38.3% of reviews100.0% of reviews — better
Number of ratings1 — better—
Update frequencyEvery 2 months — betterEvery 6 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS18.614.0 — better
Further details — not scored
Size13 MB263 MB
Age rating4+4+
Developerappdoctors UGWWF Deutschland

Customer experience

OpenSeaMap

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews47 reviews
Positive38.3%
Neutral12.8%
Negative48.9%

WWF Nautical Chart

Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

1 purchases

OpenSeaMap

One-time1
  • OpenSeaMap Professional$1.99
None

WWF Nautical Chart

No in-app purchases

Questions

Is OpenSeaMap free?
OpenSeaMap is free to download, with in-app purchases available.
Is WWF Nautical Chart free?
WWF Nautical Chart is free to download, with no in-app purchases.
Do OpenSeaMap or WWF Nautical Chart have ads?
Neither OpenSeaMap nor WWF Nautical Chart shows ads.
Which is updated more often, OpenSeaMap or WWF Nautical Chart?
OpenSeaMap ships an update every 2 months, and WWF Nautical Chart every 6 months. Most recently, OpenSeaMap was updated on October 12, 2026 and WWF Nautical Chart on October 12, 2026.

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