PAIesque

PAIesque is a privacy-first fitness tracker and live location sharer. Everything runs locally; sharing between users happens through your own server, not through Google, Strava, or any cloud provider.

Record heart rate and GPS directly from BLE chest straps and other heart rate sensors. No companion app required. Multiple sensors can be recorded in parallel, and sessions are saved as GPX and CSV for use in other tools.

Analyze your training on an interactive map and zoomable chart. View live metrics while a recording is active, or inspect past sessions by date range. The map track is colored by heart rate zone.

Share live status and completed recordings with a group through a simple self-hosted PHP server. See other group members on the map in real time and browse their past sessions the same way you browse your own. Shared payloads are end-to-end encrypted; the server stores opaque blobs and cannot read them. If you don't have a heart rate sensor, the app also works as a pure GPS location sharer — no account, no third-party service, just your own server.

Training-load metrics come from published formulas. Each formula in the app carries an evidence label so you know what is peer-reviewed, what is a professional convention, and what is a heuristic:

• TRIMP methods — Banister, iTRIMP, and LT-TRIMP.
• EWMA & ACWR — rolling load and injury-risk monitoring.
• Recovery metrics — RHR and HRV (RMSSD) from your sleep window.
• Polarized training — zone distribution and achievement tracking.

The app also includes a PAI-like score inspired by the Personal Activity Intelligence concept. It is not the official PAI algorithm — the official PAI is proprietary and commercially licensed by Mio Global. Values will differ from commercial implementations.

Data sources. Heart rate can be recorded directly from BLE chest straps and other heart rate sensors, without any companion app. If your wearable needs a companion app to sync, Health Connect handles the import. Gadgetbridge is a natural companion for users of open-source wearables — it syncs heart rate from many devices into Health Connect, and PAIesque reads from there. Garmin Connect, Polar Flow, and other proprietary companion apps also work via Health Connect. No app-specific integration is required for any of them.

Privacy is the default. No accounts, no cloud uploads, no analytics, no tracking. Data stays on your device; sharing happens only if you explicitly configure a server.