# Rubberduck: Sailing Log NMEA — The logbook that writes itself > The logbook that writes itself (iPhone/iPad app by Christian Mollerherm.) - Source: https://appshunter.io/ios/app/rubberduck-sailing-log-nmea/id6770285345 (this page in markdown: same URL + `.md`) - Developer: [Christian Mollerherm](https://appshunter.io/developer/1896730431) - Category: Navigation - Price: Free with in-app purchases - Age rating: 4+ - Requires: iOS 18.6 · 9 MB - Languages: American English, German (Germany) - Released: 2026-06-28 - Data updated: 2026-08-20 - User reviews in markdown: https://appshunter.io/ios/app/rubberduck-sailing-log-nmea/id6770285345/reviews.md ## What is Rubberduck? The logbook that writes itself: GPS track, live onboard data, weather and tides – ending in a polished PDF logbook. Built by a sailor, for everything from an evening sail to a long passage. A LOG THAT THINKS AHEAD • Automatic entries by time, distance or course change – you sail, the app writes • Seamark logging: buoys, lighthouses and beacons you pass are logged automatically • Voyages with legs, skipper, crew and distance in nautical miles • Log reading (nm) and engine hours per passage – start values carried over automatically • Start and stop with a single tap – a clear timeline for every leg NAVIGATION & ONBOARD DATA • Automatic GPS track recording with distance in NM – protected against GPS outliers • Live NMEA 0183 over Wi-Fi: wind, depth, water temperature, course, speed • Anchor watch with drag alarm – sleep easy at anchor YOUR SHIP'S LOG ON THE WEB – KIELWASSER • Publish passages to kielwasser.blog with one tap – your own ship's log with interactive chart, ad-free, your data stays yours • Boat profile with photo, optional live position – family and friends sail along from home • Shareable voyage cards for Instagram & Co. WEATHER & TIDES • 48-hour forecast: wind, gusts, rain, temperature, wave height • Sea-weather warnings from Beaufort 6 • Tidal planner: next high and low water with heights • Area news: official notices for your waters — closures, lock & bridge works, wrecks (NL, DE, DK, SE) HARBOURS, CURRENT & SAFETY • Harbour search with map, wind-shelter rating and facilities – save your area offline (Premium) • Current (set & drift) from NMEA: direction, rate, whether with or against you (Premium) • On-board barometer with trend and its own storm warning • GPS integrity: warns of interference from spoofing or jamming (Premium) • Night-watch alarm (dead-man check) and watch handover logged with one tap ORGANISED ON BOARD • Cash box: expenses, payments and a fair settlement for the crew • Watch schedule: shifts shared automatically across the crew • Ship care: maintenance, repairs and spare parts at a glance • Documents: boat papers and licences always with you • Photos with location and captions right in your logbook EXPORT & SYNC • Professional PDF logbooks – summary or detailed report with track and photos • iCloud sync: everything automatically on iPhone and iPad AND MORE • Maps: Apple Maps, OpenStreetMap, Google • 11 languages, optimised for iPhone and iPad • Your data stays private – iCloud only, no third-party server By the way: the app takes her name from SY rubberduck – the boat she was built aboard, and on which she still sails every single mile. Try it for free – then continue with an annual subscription or a one-time lifetime purchase. Fair winds! Sailing Logbook Premium is available as an annual subscription or a one-time lifetime purchase. Where offered, a free trial begins when you subscribe; afterwards your Apple ID account is charged. The subscription renews automatically for the same period unless cancelled at least 24 hours before the end of the current period. Manage or cancel in your Apple ID account settings. Any unused portion of a free trial is forfeited when you purchase a subscription. Privacy Policy: https://kielwasser.blog/privacy/ Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ ## Pricing and in-app purchases Base price: Free. **Subscriptions** | Subscription | Price | Period | | --- | --- | --- | | 30 days free | $17.99 | per year | **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Sailing Logbook Premium - Lifetime | $49.99 | one-time | ## Version history (last 5 releases) ### 4.5.8 — 2026-08-18 New and a real highlight for everyone with NMEA on board: the app now derives the current (set and drift). From the difference between speed over ground and speed through water it shows the current's direction and rate and whether it sets with you or against you - live in the NMEA monitor and in the active passage. Optionally the app logs the values to the logbook (interval under More, Tracking and Log); a current summary is added when a passage ends. Premium. Cleaner tracks too: GPS outliers (impossible jumps) are detected and kept out of the recording, and 'Clean track' removes them afterwards from existing passages - the distance is corrected. Also new for getting started: a short first-run assistant (ship, skipper, optional Kielwasser) and a guided feature tour through the app - open the manual any time via the book icon at the top. Plus stability improvements. ### 4.5.7 — 2026-08-17 This update adds polish: the currency converter is quicker to use - the amount is selected when you tap it, so you can type your number right away. The automatic seamark log entries (abeam to port/starboard) are now more accurate and are only added when the course is reliable. The offline download of the harbour search has become gentler and more reliable. New: log a watch change right from Quick Entry - the current and next watch are shown, and one tap records the handover in the logbook. Plus stability improvements. ### 4.5.6 — 2026-08-15 New: save the harbour search offline. Premium users can now download a map area of the harbour search in advance, so harbours, anchorages and charts stay available at sea without a connection. Downloads are now much faster, and when you reopen the search you can see at a glance that an area is saved and how much storage it uses. Plus stability improvements. ### 4.5.5 — 2026-08-09 This version improves GPS reliability when sailing with NMEA instruments: - When NMEA is the position source, only NMEA is now used and evaluated. No more switching to a less accurate device GPS during a trip. - The track no longer shows false spikes or gaps when the position comes from the NMEA network. - GPS integrity warning: no more false alarms on a fixed-mounted NMEA device (normal cruising, current/set or a slightly off device clock no longer trigger a warning). Genuine jamming and spoofing signals are still detected. - If NMEA drops out, the device GPS still steps in as a fallback - even during an active trip. ### 4.5.4 — 2026-08-08 This update fixes important issues and improves reliability on board: - Trip values now sync reliably across devices: final readings for the log, engine hours and the water and fuel tanks are no longer lost. - A trip's final readings carry over as the starting values of the next trip and are recorded in the logbook at the start. - GPS integrity warning: no more false alarms in locks, harbours and during slow manoeuvring; the warning reliably steps back down. - The anchor watch runs more calmly, with no false GPS warnings while the boat lies still. - Further stability improvements. ## Apps similar to Rubberduck | App | Rating | Price | Category | | --- | --- | --- | --- | | [NMEAremote LITE](https://appshunter.io/ios/app/nmearemote-lite/id413937027) | 4.7 (3) | $3.99 | Navigation | | [Anchor Sentry](https://appshunter.io/ios/app/anchor-sentry/id1422478182) | 4.0 (4) | $3.99 | Navigation | | [WinGPS Yacht Navigator](https://appshunter.io/ios/app/wingps-yacht-navigator/id6473640629) | — | Free | Navigation | | [Skippers Log](https://appshunter.io/ios/app/skippers-log/id1489815914) | — | Free | Navigation | | [SkippersNotes: Boat trip log](https://appshunter.io/ios/app/skippersnotes-boat-trip-log/id1595953469) | — | Free | Navigation | | [QuickTide](https://appshunter.io/ios/app/quicktide/id1360884661) | — | Free | Navigation | ## Related topics [sailing log](https://appshunter.io/ios/topics/sailing-log) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-20.*