HealthFactory

HealthFactory

HealthFactory transfers your Apple Health data (scale, Apple Watch, nutrition, training, symptoms) from your iPhone to this server and makes it available only to you in Claude or ChatGPT. You can then ask, for example: "How has my sleep changed over the last four weeks?" or "Show me my weight trend and protein for the last three months." The app also shows charts, the patterns behind your sleep and recovery, and more.

Everything the app does, with pictures: Features. Currently a private, invitation-only beta. No diagnoses, no ads, no selling of data.

Getting started

  1. Install the app. Install TestFlight from the App Store, then HealthFactory via the beta link from your invitation.
  2. Start. Open the app, read the privacy policy, consent to the processing and tap "Continue with Apple" (Face ID; we only receive an identifier, no name and no address). If you prefer not to use an Apple ID, choose "Start without Apple ID".
  3. Allow Health access. Tap "Allow access to Health"; in Apple's dialog tap "Turn On All", choose all data (not just 30 days) if asked, then scroll all the way down and tap "Allow". The first time, keep the app open and the iPhone unlocked until the first full sync finishes (up to 5 years of data, a few minutes). Tips on data sources, sleep and background sync: Set up Apple Health.
  4. Connect your assistant. A connector is an add-on in Claude that lets Claude read your HealthFactory data. You set it up once, most easily on a computer at claude.ai; it then also works in the Claude app on the iPhone. In our experience this also works with the free Claude plan. The address is always https://selflens.app/mcp.
    Claude (web, Mac app or iPhone)

    Settings → Connectors → Add custom connector. Name HealthFactory, URL https://selflens.app/mcp, then Connect. Claude shows a code and "Open HealthFactory": confirm it in the app with Face ID (the card "Connect with Claude" on "Today" walks you through it).

    ChatGPT (beta, depending on plan)

    Custom connections (MCP servers) are, as far as we know, only in paid ChatGPT plans (Plus, Pro, Business …) and only on the web (chatgpt.com) or desktop app, not in the iPhone app; once set up they also work on the iPhone. On chatgpt.com under Settings → Plugins (formerly "Connectors"/"Apps"), enable developer mode, create a connection with URL https://selflens.app/mcp and authentication OAuth (leave client ID and secret empty). Confirm in the HealthFactory app with Face ID (on a computer, the sign-in page shows a code to confirm in the app). Menu names change often; not yet tested with a real ChatGPT account.

  5. Go. Start a new chat and ask, e.g. "Compare my last 4 weeks with the 4 before" or "What was different from usual in the last few days?" If Claude does not look at your data on its own, add "in HealthFactory".

Good to know

What is HealthFactory for?

For healthy people aged 14 and over who want to collect, view and analyse their own data on sleep, activity, training, nutrition and body from Apple Health with an AI assistant. HealthFactory is not intended to detect, predict, monitor or treat diseases, and not for decisions about medication, diagnoses or treatment. Goals for weight, body fat and calories are available from age 18 only; the app is not suitable for weight goals with an eating disorder or during pregnancy. Claude and ChatGPT have their own age limits. If you have complaints or unusual readings, see a doctor; in an emergency call 112 (in the US 911).

Which data?

Whatever you allow in Health: body measurements (e.g. a scale), sleep, resting heart rate, HRV, activity, workouts, nutrition (from your nutrition app), symptoms, cycle and medications (allowed individually). You can also log symptoms, weight, body fat, waist circumference, blood pressure, mood, water and caffeine yourself in the app or via Claude; they are saved to Health if you allow the app to write there. Lab results, medications and supplements you log, training sessions with exercises, goals and self-experiments are stored on the server only. The app writes nothing else to Health.

Who can see my data?

You, and Claude or ChatGPT in your account after you set up the connection there (what they retrieve is stored in your chat). Other users have no access. The server operator could technically access the database; this is only done when necessary for operation. Details in the privacy policy.

What do I need?

An iPhone with iOS 26, the Health app with your data, and a Claude or ChatGPT account.

Something not working?

The most common pitfalls and their fixes: Help.

Deleting

In the app: gear icon on "Today" → Settings → Delete account. This permanently removes your account and all data. You can export all data first.