A free iOS app that syncs all of Apple Health to your own database — then gives every AI a live window into your sleep, HRV, recovery, and fitness. Works with Claude, ChatGPT, Cursor, and any MCP client.
Your HRV trended well this week — Wednesday was a standout at 71ms, your highest in 3 weeks. Here's the full picture:
avg: 65ms · range: 58–71ms · 7-day trend: ↑
Sleep was consistent (7h 10m avg). Active energy slightly below your baseline on Tuesday — rest day effect.
health4.ai syncs to any Postgres — Supabase, Neon, or a Docker container on your laptop. Run the schema, add your connection string to the iOS app, done. No subscriptions, no black-box cloud, no lock-in.
Schema file: health4.ai/schema.sql · Compatible with any Postgres 14+
Tap to authorize HealthKit. Background sync starts immediately — HKObserverQuery + BGProcessingTask push every new sample as it arrives, without opening the app.
Point the app at your Postgres: Supabase, Neon, or a local Docker container. Run the schema once. Your decade of health history lands on day one.
Add one line to your Claude Desktop or Cursor config. Then ask: "How's my sleep debt this week?" "When was my HRV last above 70?" "Am I ready to train tomorrow?"
Claude's native Apple Health connector only works on claude.ai web. health4.ai also works with Claude Code, the Claude API, ChatGPT, Cursor, and any tool that supports MCP.
The iOS app backfills your full Apple Health archive on first sync — every step, heartbeat, and workout going back to when you first wore a wearable.
HKObserverQuery fires the moment Apple Health gets a new sample. Your AI always has fresh data without you doing anything.
Your health data syncs to a Postgres database you control. We don't store a copy, sell it, or have access to it. GDPR-friendly by construction.
One email when it's on the App Store. No spam, ever.