SEAiq vs app4sail
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
- 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
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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/
app4sail
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Nautical navigation app. uses free S57 vector charts Not everywhere in the world those maps are available and not all of the available maps are implemented at this moment. Instead you can use maps of the project 'Openstreetmap'
Screenshots
Verdict
The clearest difference is price: SEAiq at Free against app4sail's $4.99. SEAiq also leads on update cadence (every 3 weeks vs every 4 months). app4sail's advantage is in-app purchases (none vs 1) and iOS requirement (12.0 vs 15.0). On 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
SEAiq is free to download; app4sail costs $4.99 up front. SEAiq sells 1 one-off in-app purchase. app4sail asks for nothing beyond the download.
SEAiq ships an update every 3 weeks, app4sail every 4 months. The most recent releases landed on September 24, 2026 and June 7, 2026 respectively.
| Parameter | SEAiq | app4sail |
|---|---|---|
| Price | Free — better | $4.99 |
| Rating | 4.7 (193 ratings) — better | — |
| Positive reviews | 61.3% of reviews | — |
| Number of ratings | 193 — better | — |
| Update frequency | Every 3 weeks — better | Every 4 months |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.0 | 12.0 — better |
| Further details — not scored | ||
| Size | 53 MB | 10 MB |
| Age rating | 4+ | 4+ |
| Developer | Sakhalin | anton van oosten |
Bugs and 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
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- 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
app4sail
Not enough reviews yet to summarise bugs or requests.
In-app purchases
SEAiq
- Upgrade for Premium Features$49.99
app4sail
No in-app purchases
