Open-source wearables and health

4 wearables and health whose code is public under an OSI-approved license, rated for privacy with evidence. Picks first, then by score.

1. AsteroidOS Grade B

   Open source Linux distribution for smartwatches that replaces Wear OS on supported watches, with the AsteroidOS Sync companion app for Android.

   GPL-2.0 for the core, and the AsteroidOS Sync app is GPL-3.0. Some watches rely on proprietary hardware drivers from the original Android firmware. Source code

2. Gadgetbridge Grade B

   Open source Android app that connects smartwatches and fitness trackers to your phone without the vendor app or cloud account.

   AGPL-3.0 and Apache-2.0. Source code

3. InfiniTime Grade B

   Open source firmware for the PINE64 PineTime smartwatch, with notifications, step counting and heart rate over Bluetooth through companion apps such as Gadgetbridge.

   GPL-3.0. Source code

4. Bangle.js Grade D

   Open source, hackable smartwatch from Espruino that runs JavaScript apps, with an app loader in the browser and an Android companion based on Gadgetbridge.

   MPL-2.0 firmware. Apps in the BangleApps repository are MIT. Source code

Compare all 7 wearables and health, open source or not.