Google Health Connect API integration

Health Connect is Android's on-device health data store and the successor to Google Fit. This matters urgently: the Google Fit APIs have been deprecated, and products still calling them are on a clock.

Like HealthKit, Health Connect is on-device. There is no cloud endpoint to call, so an Android app is a prerequisite. Unlike HealthKit, it is a separate system component rather than a built-in framework, which means availability varies by Android version and by whether the user has it set up.

WearLink's Kotlin SDK reads Health Connect records and pushes them into the same normalised pipeline as the cloud providers. If you are migrating off Google Fit, this is the replacement path.

Connect a Google Health Connect user

Two calls. The first mints a hosted connect URL for your end-user; the second reads the normalised summaries once they have authorised with Google Health Connect. Subscribe a webhook to receive the same objects as they land.

# 1. Create a connect session for your end-user
#    The API key goes in X-WearLink-API-Key, not in Authorization.
curl -X POST https://wearlink.io/api/v1/connections/session \
  -H "X-WearLink-API-Key: $WEARLINK_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"user_id": "'"$USER_ID"'", "provider": "google-health-connect", "redirect_uri": "https://yourapp.com/connected"}'

# → { "connect_url": "https://wearlink.io/widget/connect?token=...", "expires_in": 3600 }
# Redirect the user there; they authorise google-health-connect and land back on your redirect_uri.
# The token is scoped to that one user — it is safe to put in a browser URL.

# 2. Pull normalised data whenever you want
curl -H "X-WearLink-API-Key: $WEARLINK_API_KEY" \
  "https://wearlink.io/api/v1/users/$USER_ID/summaries?provider=google-health-connect&days=7"

Google Health Connect data available through WearLink

• Steps
• Heart rate
• Sleep
• Workouts
• Whatever else the user grants

Webhook events you can subscribe to

• steps.created
• heart_rate.created
• sleep.created
• workout.created

Normalised families this provider feeds: Sleep, Heart Rate Variability, Heart Rate, Workouts, Steps & Daily Activity, Calories & Energy, Blood Glucose & CGM, Blood Pressure, Body Composition, Nutrition & Energy Balance.

What makes the Google Health Connect API hard to integrate directly

These are the things that turn an estimated one-week integration into a one-month one.