Free your wearables from vendor clouds — use smartwatches and bands with a fully local, open-source app.
Local wearable companion. Data never leaves the phone; Bluetooth/location permissions are required for device discovery and sync.
Gadgetbridge replaces the proprietary companion apps for a huge range of wearables — Pebble, Mi Band and Amazfit families, Garmin, Fossil, Huami, and dozens more. Device data is stored locally on your phone instead of being uploaded to the manufacturer's cloud. Features depend on the device but cover activity tracking, heart rate, sleep, notifications to the watch, music control, weather sync, watchface and app installation where the hardware allows, and full data export. It is open source (AGPL-3.0), donation-funded, and community-documented device-by-device. Bluetooth permissions map directly to device communication — there is no account, no vendor cloud, and no ads.
Gadgetbridge by Freeyourgadget — Health & Fitness app, 22 MB, requires Android 5.0+. Direct APK download on AppsDone, scanned for malware.