No cloud API; data stays in HealthKit on your iPhone, readable by apps you authorise. The Health app can export all health data as an archive.
⭐ Flagship deep dive
Very private, but your data is locked to the iPhone.
🔌 Official API
- There is no cloud/web API. HealthKit is an on-device iOS framework: apps you authorize, per data type, can read and write it on your iPhone.
- For any server-side use you need an iOS app that reads HealthKit and pushes the data out.
📦 Export
- Health app → profile picture → Export All Health Data creates export.zip.
- Inside: export.xml (every HealthKit record with type, value, unit and timestamps), export_cda.xml (HL7 CDA), plus workout routes as GPX.
- It is a manual, phone-only export with no scheduling. The files can be multiple GB.
🏠 Home Assistant
- There is no official integration, and the HA Companion app can't read Health data.
- The common route is the paid third-party app Health Auto Export, which POSTs JSON to HA's REST API with a long-lived token. iOS only lets it run while the phone is unlocked.
💳 Subscription
- No subscription is needed for data or export. Apple Fitness+ is optional content.
- The costly part of the lock-in is that the watch requires an iPhone.
🔒 Privacy notes
- Health data is processed on the device. When synced to iCloud it's end-to-end encrypted, as long as you use two-factor authentication and a passcode.
- Apps get per-type, revocable permissions (Settings → Health → Data Access & Devices).
Score breakdown
Official APIVia phone health platform · 5/25
Data exportFull account export · 15/25
Gadgetbridge / open firmwareNot supported · 0/20
Home AssistantNone · 0/15
SubscriptionNot needed · 15/15
Quick answers
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Sources
- Apple HealthKit
- Apple: Share/export your health data
- Apple: iCloud data security overview (Health end-to-end encrypted)
- Health Auto Export → Home Assistant guide
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📬 The Data Ownership Digest
Occasional email: API changes, export deadlines, and new scorecards.
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