Pelorus Nav

From the App Store Source

Pelorus Nav is a free, open-source marine chartplotter for iPhone and iPad. It draws official NOAA electronic navigational charts as crisp vector charts, using the standard IHO S-52 symbology of professional chartplotters. Once you've downloaded a region, everything works offline, far from cell service. No account, no ads, no subscriptions, no tracking. Your routes, tracks and position stay on your device. CHARTS • Official NOAA vector charts (ENC) for US coastal waters, the Great Lakes, Puerto Rico and the US Virgin Islands, and Hawaii, in downloadable regions • Kept current: NOAA's updates are checked nightly, and the app tells you when a downloaded region has newer charts • Seamless multi-scale quilting, with more detail appearing as you zoom in • Day, Dusk, Night and E-ink themes in the official S-52 color palettes • Depth shading set to your boat's draft, with a safety contour • Light sectors, charted currents, adjustable detail level and text size • Offline street map for land detail near shore • Tap any buoy, light, wreck or depth area to see its details • Find harbors, islands, buoys and lights by name, even offline NAVIGATION • Tap to build routes, drag to edit, snap to existing waypoints, reverse and extend • Follow a route leg by leg, with an arrival alert and automatic advance to the next leg • Large, readable instruments: speed and course over ground, VMG, bearing, steer-to, distance and time to waypoint and destination, and ETA • Projected course line with time ticks • Follow, course-up and north-up modes; magnetic or true bearings • Crew-overboard button: press and hold to drop a mark and navigate back to it • Touchscreen lock, so spray and stray taps can't change anything under way TRACKS • Record every outing; recording continues in the background with the screen off • Track Viewer with a speed-colored track, speed chart, fast playback, and tack and jibe detection • Stats for any stretch: distance, time, average and top speed • GPX import and export for routes, waypoints and tracks TIDES, CURRENTS, WIND & SUN • NOAA tide and current predictions, computed on your device so they work offline • 48-hour time bar to see tides, currents and wind ahead • Wind forecast barbs (internet connection required) • Sunrise, sunset and twilight times TRADITIONAL PLOTTING • Fixes, DR, EP and running fixes; bearing lines, distance arcs, current arrows and notes. Chartwork the way you learned it. GPS & INSTRUMENTS • Your iPhone or iPad's own GPS • Bluetooth LE GPS receivers • Your boat's Signal K server on the local network (experimental) • Built-in simulator for exploring the app from shore Pelorus Nav is an aid to navigation and planning. It is not a substitute for official charts, a proper lookout, and prudent seamanship. Free and open source under the MIT license.

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