health4ai

health4ai moves the health data on your iPhone into a database you own, so any AI assistant can answer questions about it. The Health app holds years of your sleep, HRV, heart rate, workouts and 150+ other metrics, but nothing outside your iPhone can read it. health4ai is the bridge. It syncs HealthKit into a Postgres database you control, and any MCP-compatible AI client can then query it in plain language. BEFORE YOU START This app needs a Supabase project that you create and own. The free tier is enough. Setup takes about five minutes and the app walks you through it. There is no health4ai account and no health4ai server. WHAT IT DOES Syncs sleep stages, HRV, resting and walking heart rate, steps, distance, workouts, active energy, VO2 max, respiratory rate, body mass and more. Backfills your full history, not just today. If you have worn a watch for a decade, a decade goes in. Picks up exactly where it left off each time you open it, so catching up is never a manual export. Tells you plainly when a metric is not being shared with the app, instead of showing you an empty chart and calling it complete. Lets you choose Essentials or every supported type when you set it up, and change your mind later. YOUR DATA STAYS YOURS health4ai never receives, stores or transmits your health data. It travels from your iPhone to your database and nowhere else. No analytics on your health data, no advertising, no third-party sharing, no resale. The iOS app and the companion MCP server are both open source under the MIT license, so you can read exactly what they do. WORKS WITH Any AI client that speaks the Model Context Protocol, through the companion open-source MCP server. Eight purpose-built tools cover daily snapshots, trends, baselines, sleep, workouts and free-text search across your records. FREE No subscription, no in-app purchases, no account, no upsell.