Red Grid MGRS
Free app replacing the military's $2,500 DAGR GPS
What it does
The military's DAGR (AN/PSN-13) costs $2,500 and runs a UI from 2003. Red Grid MGRS puts the same land nav in your pocket — live 10-digit MGRS, dead reckoning, resection, pace count, declination, waypoints, 6 radio report templates, and NATO voice readout. Built with React Native, fully offline, zero tracking. The algorithms are all public domain — one dev built this in months. Open source on GitHub.
Does the same job
all alternatives →- RGRed Grid Link – peer-to-peer team tracking over Bluetooth, no serversMar 2026 · github.com · ▲54
I go on a lot of backcountry trips where I barely get cell service. If my group splits, nobody knows knows where anyone is until you regroup at camp or at your destination. You can buy Garmin radios or try to set up an ATAK, but ATAK is Android-only and assumes you have a TAK Server running somewhere to make use of all of the functionality. Cool tools themselves, but expensive to set up correctly. I just wanted two iPhones to share their location directly over Bluetooth when cell coverage was lacking. Red Grid Link does that. Start a session, and anyone nearby running the app shows up on…
- OSOpen-Source International Space Station Tracker ESP32/Arduino for $202025 · github.com · ▲75
International Space Station Tracker on an ESP32 CYD (Cheap Yellow Display) costing $20. Live update over Wifi, touchscreen, backlight power management. Cheap and interesting classroom STEM project. Fully open source.
- FDFOSS De-googled Compass and Nav app with live location trackingNov 2025 · github.com · ▲5
MBCompass: A popular modern FOSS Compass and Navigation app without Ads, IAP, or Tracking New Release: MBCompass v1.1.12 This release and upcoming ones follow the feature roadmap proposed in the v2 design proposal. Features: - Shows clear cardinal direction and magnetic north as well as true north. - Displays magnetic strength in µT. - Live GPS location tracking on OpenStreetMap. - Sensor fusion for improved accuracy (accelerometer, magnetometer, gyroscope). - Light and dark theme support is controlled via Settings. - Keeps the screen on during navigation. - Landscape orientation supports -…
GridConvertProJun 2026 · gridconvertpro.com · ▲2Convert GPS coordinates between every format, free ⭐
More dev tools this month
the category →
The first open-source price index for GPU compute
Dev tools · 10d ago · getcomputable.com
OpenTrailPaper is open-source bike computer firmware for the LilyGO T5S3 4.7" E-Paper PRO. It supports offline maps, GPX routes, FIT recording and Bluetooth sensors.
Dev tools · 2d ago · opentrailpaper.com
Open-source GTM skills for technical founders
Dev tools · 29d ago · gtmcofounder.com
Launched alongside, March 2026
the whole month →
Switch from ChatGPT to Claude with import memory feature
AI · Mar 2026 · claude.com
