NMEA Mapper 3D

Turn the fish finder you already own into a 3D depth map of the seabed.

NMEA Mapper 3D reads depth and GPS from your boat over Wi-Fi and builds your own bathymetry map as you drive: a detailed 3D chart of every ledge, drop-off, reef and pinnacle you pass over. Your fishing spots stay private on your phone. No extra sonar to buy, no subscription.

YOUR OWN 3D DEPTH MAPS

• Press Record and watch the seabed take shape behind your boat, sounding by sounding

• Explore lake and sea bottoms in 3D: tilt, turn and zoom over structure, wrecks and drop-offs

• Depth colours or a textured seabed, with contour lines from 1 to 100 m, ft or fathoms

• See on the chart exactly where you have mapped, and dive into 3D anywhere you have been

LIVE DEPTH SONAR

• A fish finder style depth history over 1, 2 or 10 minutes

• Scroll back, tap any moment to see the depth and where it was, then mark that spot

• The bottom ahead along your course, drawn from your own depth map

• Shallow-water alarm, minimum and maximum depth, water temperature

FISHING MAP, CHARTS & SEAMARKS

• Street chart or satellite map with buoys, lights and harbour marks from OpenSeaMap

• Areas you have viewed are kept for offline use on the water

• Follow your boat north-up or heading-up, rotate the map with two fingers

MARK YOUR FISHING SPOTS

• GPS waypoints for fish, schools, reefs, wrecks, hazards, anchorages and pins

• Species, colour, notes and depth for every mark, with distance from your boat

• Import and export your marks as GPX

EVERY TRIP SAVED

• Each recording becomes a GPS track with its depths, distance and time

• Share any track with its depths as GPX

CATCH LOG

• Log species, length, weight, bait and a photo in seconds

• Depth, water temperature, moon phase and bite period are filled in for you

• Insights show what your best fishing days have in common

BITE TIMES & SOLUNAR CALENDAR

• Major and minor bite periods for your fishing spot

• Sunrise, sunset, moonrise, moonset and moon phase

• Reminders before the next bite period

DEPTHS YOU CAN TRUST

• Transducer depth and keel offset, depth below the surface, transducer or keel

• Tide correction: automatic from nearby tide stations where available, or set by hand

WORKS WITH YOUR BOAT'S ELECTRONICS

NMEA Mapper 3D connects to any NMEA 0183 source over Wi-Fi (TCP or UDP): a Wi-Fi gateway or multiplexer, or a chart plotter or fish finder with Wi-Fi NMEA output. NMEA 2000 networks work through a gateway that sends NMEA 0183 over Wi-Fi. The app finds your source automatically and reads depth (DBT, DPT), GPS position, speed and course (RMC, GGA, GLL, VTG), heading (HDT, HDG, HDM) and water temperature (MTW).

For accurate depth maps, depths are recorded only with GPS from your boat's NMEA feed. Without it, your phone's GPS still shows where you are.

PRIVATE BY DESIGN

No account and no uploading. Your depth maps, fishing spots, tracks and catches stay on your device.

FREE FISHING APP, NO SUBSCRIPTION

Every feature is free, supported by ads. Remove the ads for good with a one-time purchase.

Day, dusk and night display modes for boating day and night. Metres, feet or fathoms. Phones and tablets.

Important: NMEA Mapper 3D is a fishing and mapping aid. It is not a certified navigation system and does not replace official nautical charts, a chart plotter or good seamanship.