Comparison

OpenSeaMap vs SEAiq

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

SEAiq

This marine navigation app offers comprehensive charting capabilities, allowing users to load various standard chart formats and download NOAA charts. It includes essential navigation tools like waypoints, routes, and an anchor alarm, along with weather overlays and NMEA/AIS integration.

Highlights
  • Load custom S-57, S-63, iENC, BSB, KAP charts
  • Automatic NOAA chart downloads
  • Waypoints, routes, and tracks
  • Anchor alarm
  • Automatic weather downloads
  • NMEA and AIS integration
Read full description

SEAiq is a full-featured marine navigation app. It lets you load your own charts in standard formats, including S-57, S-63, iENC, BSB, and KAP. It also automatically downloads charts from NOAA for the United States. Features include: * Waypoints * Routes * Tracks * Night color modes * Anchor alarm * Automatic download and display of weather (wind & isobar) * Chart measuring tools (EBL/VRM) * Wi-Fi-based NMEA and AIS No purchase is required to view charts. Premium navigation features are enabled during a 7-day evaluation period. After that, an annual subscription is required. Existing one-time purchases retain the features they unlocked. Continued use of GPS running in the background can dramatically decrease battery life. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

OpenSeaMap4 screens
SEAiq2 screens

Verdict

The call

The clearest difference is rating: SEAiq at 4.7 against OpenSeaMap's 1.0. SEAiq also leads on ratings volume (194 vs 1) and review sentiment (61% vs 38%). On price, ads, in-app purchases and monetization model 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 and SEAiq sells 2 in-app purchases, starting at $15.00 per year. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

SEAiq holds the better App Store score, 4.7 against 1.0. That said, the two scores are not equally well evidenced: SEAiq has 194 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 38% of OpenSeaMap's written reviews are positive against 61% of SEAiq's.

UpkeepUpdate frequency

OpenSeaMap ships an update every 2 months, SEAiq every 3 weeks. The most recent releases landed on October 21, 2026 and October 29, 2026 respectively.

Scorecard5 real differences · 5 level
OpenSeaMap versus SEAiq: the parameters behind the verdict, then further details
ParameterOpenSeaMapSEAiq
PriceFreeFree
Rating1.0 (1 ratings)4.7 (194 ratings) — better
Positive reviews38.3% of reviews61.3% of reviews — better
Number of ratings1194 — better
Update frequencyEvery 2 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS18.615.0 — better
Further details — not scored
Size13 MB54 MB
Age rating4+4+
Developerappdoctors UGSakhalin

Customer experience

OpenSeaMap

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

SEAiq

All ratings194 ratings
Positive91.8%
Neutral3.6%
Negative4.6%
Written reviews75 reviews
Positive61.3%
Neutral6.7%
Negative32.0%

Bugs and requests

OpenSeaMap

Not enough reviews yet to summarise bugs or requests.

SEAiq

Reported bugs

4 issues
  • No access to premium features after payment
  • Chart downloads fail if app is not on screen
  • App freezes when trying to delete
  • App crashes

Requested features

13 requests
  • Simplify course plotting
  • Add support for .MBTiles
  • Add VMG feature
  • Add support for .MBTiles
  • Add support for .MBTiles
Show 8 more
  • Allow selection of discreet chart areas
  • Add GPS data from TCP/IP source
  • Allow disabling internal GPS
  • Provide good integration/complement to OpenCpn
  • Provide TCP/IP support for NMEA data
  • Broadcast waypoint and NMEA data to external systems
  • Lower price for waypoints creation
  • Allow using purchased charts across devices

In-app purchases

1 purchases

OpenSeaMap

One-time1
  • OpenSeaMap Professional$1.99
2 purchases

SEAiq

Subscriptions1
  • Premium Annual$15.001 Year
One-time1
  • Upgrade for Premium Features$49.99

Questions

Is OpenSeaMap free?
OpenSeaMap is free to download, with in-app purchases available.
Is SEAiq free?
SEAiq is free to download, with in-app purchases available.
Which has better reviews, OpenSeaMap or SEAiq?
SEAiq is rated higher. OpenSeaMap averages 1.0 out of 5 from 1 ratings, while SEAiq averages 4.7 from 194 ratings.
Do OpenSeaMap or SEAiq have ads?
Neither OpenSeaMap nor SEAiq shows ads.
Which is updated more often, OpenSeaMap or SEAiq?
OpenSeaMap ships an update every 2 months, and SEAiq every 3 weeks. Most recently, OpenSeaMap was updated on October 21, 2026 and SEAiq on October 29, 2026.

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