MARLOG.From coastal waters to everything at sea.
An atlas of 11,000+ charted coastal places — any coast on Earth — sailing-window meteorology, a seamanship academy, and an AI compass. Free on iOS.
±0.1° magnetic declination auto-compensation and inertial sensor fusion for coastal passage.
ECMWF & GFS multi-model wind, swell period, sea state, and intelligent sailing window calculations.
Sheltered anchorages, seabed holding data, depth contours, and port VHF channels offline.
Natural voice passage planning, COLREGS collision advice, and seamanship intelligence.
MARLOG. Everything a coastal mariner needs, in one instrument.
An atlas of 11,000+ charted places, a seamanship academy, marine forecasts with sailing windows, and an AI compass — the whole chart table in your pocket.
MARLOG. Everything a coastal mariner needs.
Atlas of 11,000+ charted places, seamanship academy, forecasts, and AI compass.
Atlas
The coast, charted.
MARLOG's Atlas charts 11,000+ ports, anchorages, beaches, ancient sites and lighthouses on one dark map — and fills in any coastline on Earth on demand.
Academy
Seamanship, a few minutes a day.
MARLOG's Academy teaches seamanship through 16 courses, nearly 100 lessons and 288 practice exercises, backed by a 247-term maritime dictionary that works offline.
Forecast
The sea, hour by hour.
MARLOG's Forecast reads wind, waves, sea temperature and current for any point at sea, pairing Apple Weather with Copernicus marine models as fine as 500 m.
Compass
Ask the sea anything.
MARLOG's Compass is a maritime AI assistant that answers weather, place and seamanship questions using live data for your position.
From the log.
Technical notes, passage planning analyses, and dispatches from the team building MARLOG.
Quick answers.
What is MARLOG?
MARLOG is an iOS app for coastal mariners: an atlas of 11,000+ charted coastal places, marine forecasts with hourly sailing windows, a seamanship academy, and a position-aware AI assistant — four surfaces in one instrument.
Is MARLOG free?
Yes. Every feature is free. The optional Supporter subscription unlocks nothing — it simply backs the work.
Which coasts does it cover?
Every coast on Earth. The coasts of Türkiye are charted in the greatest depth, and any other coastline fills in on demand as you explore it.
Can I navigate with it?
No — MARLOG is a discovery, learning and reference instrument, not a navigation system. Always carry official charts and use official sources for navigation decisions.
When does it launch?
MARLOG is in App Review now. Join the launch list at the bottom of this page and you will hear the moment it is live on the App Store.