Garmin, Oura, Whoop, and Apple Health each speak a different data dialect, and Open Wearables translates all of them into one consistent REST API that you host yourself. Users authorize through a connection link or the connect widget, history backfills on the first sync, and heart rate, HRV, SpO2, sleep, workouts, and meals land in one normalized schema. When two devices record the same night, configurable data priorities decide which provider and device type wins. Native iOS, Android, Flutter, and React Native SDKs push Apple Health, Samsung Health, and Health Connect data from the phone, and full Apple Health XML exports can be imported too. Outgoing webhooks announce new data with signed payloads, test events, and delivery logs, while a live sync stream shows every pull as it happens. The developer portal adds a dashboard, user profiles with sleep, meals, scores, and women's health tabs, sync history, data coverage, API keys, team invitations, retention policies, and a seed data generator. Sleep and resilience scores ship with open algorithms you can audit and tune. An MCP server lets Claude Desktop or Cursor answer questions such as how a user slept last week. Use it for AI health coaches, fitness coaching apps, healthcare platforms, research cohorts, or a personal health archive with n8n automations on top. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.