
ReefMap: Marine Navigation
Offline charts, GPS & anchor
0 ratings
Free
In-App Purchases
Rating summary
About
ReefMap is offline-first marine navigation for boaters, fishers, divers, and reef explorers. Download your waters once and navigate with no signal — nautical charts, GPS, and the safety tools you actually need — free forever.
WORKS OFFLINE
Save an OpenStreetMap and OpenSeaMap region for use miles offshore — charts, your GPS position, waypoints, tracks, and routes. No cell signal required. Satellite imagery and Ocean relief require internet and are not included in offline downloads.
CHARTS & POSITION
• Satellite imagery from Esri as the default view (requires internet), or switch to the OpenStreetMap chart
• OpenSeaMap nautical seamarks layered on top, with an opacity slider
• Optional Ocean relief (NASA): satellite-derived land imagery and shaded seafloor relief from August 2004 for regional overviews. Requires internet; limited detail, without depth queries or detailed reef and fishing layers
• Live GPS position, speed over ground, and course
• Coordinates always on screen — DMS, decimal degrees, or UTM; tap to copy
• Full-screen digital compass with true and magnetic heading
PLAN & NAVIGATE
• Drop waypoints with marine icons and categories — reefs, wrecks, anchorages, fishing marks, harbors
• Record GPS tracks and replay your route home
• Build multi-leg routes, or draw one on the chart with your finger, and follow it with live cross-track error and arrival alerts
• Trip computer: SOG, COG, VMG, trip distance and time, plus a barometric-pressure trend for weather awareness
• Tide predictions for US waters — highs, lows, and the current level from the nearest NOAA station
SAFETY — ALWAYS FREE
• Anchor alarm — set a swing radius and get alerted if you drag, even with the screen off
• Man Overboard (MOB) — one tap drops a mark and switches to bearing-and-distance back to the spot
• Night mode — a red-light helm palette that protects your night vision
• Keep-screen-awake while you navigate
YOUR DATA, YOUR DEVICE
• Export waypoints and tracks as GPX
• Everything is stored on your device
• Built for iPhone and iPad
FREE CORE, OPTIONAL PRO
Most chart apps cost $50–$150 every year. In ReefMap every safety tool is free forever — anchor alarm, Man Overboard, night mode, GPS, compass, waypoints, tracks and routes — and your first offline region is free too. ReefMap Pro is an optional upgrade that adds unlimited offline map downloads plus anchor-watch history and named anchorages. Choose Annual ($19.99 a year, with a 2-week free trial for new subscribers), Monthly ($3.99 a month), or a one-time Lifetime purchase ($49.99). Subscriptions renew until cancelled; manage or cancel anytime in your Apple Account settings. Lifetime covers every Pro feature that runs on your device, forever; future live data, such as worldwide tides and weather, will need a subscription. It's built on free public marine data (OpenStreetMap, OpenSeaMap), so there are no recurring chart-license fees to pass on to you.
ON THE WAY
Tides outside US waters, depth contours, reef-health overlays, and live weather are in development. The safety core always stays free.
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ReefMap is intended as a navigation aid only. It should not be used as a primary means of navigation. Always carry and use official nautical charts and maintain a proper lookout. Map data is derived from public sources and may be incomplete or inaccurate.
Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy Policy: https://reefmap.stevcodes.com/privacy
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What's New in ReefMap
1.0.0
October 24, 2026
3
Subscriptions & In-App Purchases
Pro Annual
Unlimited offline charts and anchor history, yearly
$19.991 Year
14 Days trial






