Offline global coastline maps for sailors, boaters, and coastal explorers. Measure distances, find the nearest shore — no internet required at sea.
Built for real ocean conditions — where connectivity is a luxury, not a given. CoastNav works entirely offline once the maps are downloaded.
High-detail coastline and land polygon maps for the entire world, stored on your device. No cell signal needed — ever.
Tap anywhere on the map to instantly see bearing and distance to the nearest coastline point — in nautical miles or kilometers.
Survey multiple coast distances from any position simultaneously. All bearings and distances displayed in a clean, organized panel.
Center the map on your current location instantly. Coordinates displayed in degrees, minutes, and seconds format.
Choose from detail levels z7 to z12 — from ocean-scale overview to high-resolution coastal detail. Download only what you need.
Optimized dark theme for night watches, light theme for bright conditions, and auto-sync with your device system preference.
One-shot GPS requests, not continuous tracking. Tile rendering is hardware-accelerated. Designed for long passages with no charger.
One Premium purchase shared across your entire Apple family group. Crew member on another device? They're covered.
Toggle between nautical miles (NM) and kilometers for all distance measurements. The app remembers your preference.
No account. No sign-in. No subscription. Just download and go.
Download CoastNav free from the App Store or Google Play. No registration required.
Choose your detail level (z7–z12) and download coastline tiles over Wi-Fi. One-time download, works forever offline.
Open the map, tap the locate button to center on your GPS position, then hold anywhere to measure coast distances.
See bearing and distance to the nearest coastline points, displayed on-map with a clean detail panel.
Whether you're planning a passage, caught in changing weather, or simply want situational awareness — CoastNav instantly calculates bearing and distance to the nearest coastline from any point on the map.
Hold on any ocean position to activate surveying. CoastNav draws bearing lines to the nearest coastline points and presents them in an organized measurement sheet — complete with distance and bearing for each line.
Coastline data is sourced from the OpenStreetMap global dataset — the same trusted open-data foundation used by many professional mapping services worldwide.
© OpenStreetMap contributors. Data licensed under ODbL v1.0.
No subscriptions. No hidden fees. Pay once, sail forever.
Prices may vary by region. All payments processed securely by Apple App Store. Refund policy applies.
CoastNav is built with a privacy-first philosophy. We don't create accounts, don't track you, and don't share anything with third parties.
Zero sign-up, zero email, zero password. Just install and use.
No analytics SDK, no advertising ID, no behavioral tracking whatsoever.
GPS accessed only when you tap the locate button. Never in background.
All data stays on your device. Nothing uploaded to our servers.
Built with Apple's native frameworks only. No hidden data pipelines.
We never see your card details. All billing via Apple's secure system.
Read our full Privacy Policy and Terms of Service.
Free 30-day trial. No account needed. Works everywhere — even in the middle of the ocean.