Red Grid Link

Your team. Your grid. No cell towers required.

Inspired by military blue force tracking systems like ATAK, Red Grid Link brings encrypted team coordination to civilian and professional teams -- without cell towers, accounts, or servers. Track your team's positions in real time over Bluetooth, navigate with military-grade MGRS precision, and operate completely offline.

Red Grid Link is an offline-first, MGRS-native coordination platform for small teams (2-8 people) operating beyond reliable cell service. It combines precision land navigation with Field Link -- zero-config proximity sync over Bluetooth (iOS Multipeer / Android Nearby). Lightweight where ATAK is complex. Cross-platform where ATAK is Android-only. Zero infrastructure where ATAK requires TAK Server.

FIELD LINK -- TEAM SYNC WITHOUT INFRASTRUCTURE:
Field Link is what sets Red Grid Link apart. Devices within proximity automatically discover each other and share encrypted position and marker data -- no internet, no configuration, no pairing codes. Just turn it on and your team appears on the map.
- BLE proximity (iOS Multipeer/Android Nearby) transport (cross-platform)
- AES-256-GCM encrypted sync with ECDH ephemeral session keys
- Compact delta payloads (under 200 bytes per position update)
- Tiered session security: Open (auto-join), PIN (4-digit), or QR code
- Ghost markers: see last-known positions when teammates move out of range
- Time-decay visualization: full opacity fades to outline over 30 minutes
- Velocity vectors project teammate movement direction at disconnect
- Snap-to-live animation on reconnect
- Expedition Mode: under 3% battery per hour (BLE-only, 30-second updates)
- Ultra Expedition Mode: under 2% battery per hour (BLE-only, 60-second updates)
- Auto-reconnect with exponential backoff on disconnect

MGRS-NATIVE NAVIGATION:
Built on the proven MGRS engine from Red Grid MGRS -- the same coordinate system used by NATO forces worldwide.
- Live MGRS coordinates (4/6/8/10-digit precision)
- MGRS grid overlay on offline maps (GZD to 100m resolution)
- Bearing, distance, and dead reckoning tools
- Magnetic declination (WMM model)
- NATO phonetic voice readout for hands-free grid calls

11 TACTICAL TOOLS:
- Dead Reckoning plotter
- Two-point Resection
- Pace Count tracker
- Bearing calculator with back azimuth
- Coordinate Converter (MGRS, lat/lon, DMS, UTM)
- Range Estimation (mil-relation formula)
- Slope Calculator (percentage and angle)
- ETA / Speed Calculator
- Magnetic Declination converter
- Celestial Navigation (sun/moon bearing reference)
- MGRS Precision Reference

OFFLINE MAP SYSTEM:
- Downloadable map packs from USGS Topo and OpenTopoMap
- Full offline operation -- maps cached locally as MBTiles
- MGRS grid lines rendered as a dynamic overlay at all zoom levels

4 OPERATIONAL MODES:
One engine, four presentation layers. Terminology, icons, and quick actions adapt to your mission:
- Search & Rescue -- sector assignments, clue markers, search patterns
- Backcountry -- camp, waypoint, and trail navigation
- Hunting -- stand locations, game sightings, property boundaries
- Training -- exercise objectives, rally points, phase lines

AFTER-ACTION REPORTS:
One-tap PDF export containing map snapshot, mission timeline, track data, timestamps, team roster, markers, and session log.

4 TACTICAL DISPLAY THEMES:
- Red Light: preserve night-adapted vision (free)
- NVG Green: night observation device compatibility (Pro)
- Day White: high-contrast for daylight (Pro)
- Blue Force: tactical blue display (Pro)

BUILT FOR THE FIELD:
- Glove-friendly UI with 44px+ minimum touch targets
- 3-tap maximum to any primary action
- Haptic feedback on key interactions
- Accelerometer-based step detection for hands-free pace counting
- Landscape and portrait support
- Background location updates with battery drain projection

ZERO FOOTPRINT PRIVACY:
- No accounts. No sign-up. No login.
- No cloud sync. No analytics. No tracking.
- No ads. No third-party data SDKs.

Recent changes:
RED GRID LINK IS NOW PART OF RED GRID MGRS

Every Pro feature is now unlocked, free: all themes, unlimited offline map regions, AAR export, and 8-device Field Link sessions.

Link keeps working on your device, but this is the final update. New development continues in Red Grid MGRS.