Android Health Connect Integration Guide

Overview

This guide walks you through the complete integration of the Open Wearables Android SDK into a native Kotlin application, from backend setup to production deployment.

Set up backend authentication endpoint

Initialize and configure the SDK

Implement sign-in flow

Select health provider

Request health permissions

Start background sync

Authentication Architecture

The SDK supports two authentication modes: token-based (recommended) and API key. The token-based flow keeps your App credentials safe on your backend:

Your Backend generates token

Your backend calls the Open Wearables API with your App credentials (app_id + app_secret) to generate a user-scoped token (server-to-server, HTTPS) via Create User Token endpoint. Open Wearables returns access_token + refresh_token.

Your Backend returns tokens to the app

Your backend exposes its own custom endpoint that forwards the access_token and refresh_token to the mobile app. Never expose app_id or app_secret to the client.

Mobile App calls SDK signIn

The Android app receives the tokens and passes them to sdk.signIn(accessToken, refreshToken).

SDK stores & syncs

Android SDK stores credentials in EncryptedSharedPreferences and uses accessToken to sync health data directly to Open Wearables.

Never embed your app_id / app_secret in the mobile app. App credentials should only exist on your backend server. Only the access_token and refresh_token are passed to the mobile app.

Step 1: Backend Setup

Your backend needs a single endpoint that generates access tokens for your users by calling the Open Wearables API and forwarding the tokens.

Generate Access Token

When a user wants to connect their health data, your backend should:

Authenticate the user (your own auth system)
Call Open Wearables API at POST /api/v1/users/{user_id}/token with your App credentials
Return the access_token and refresh_token to the mobile app

Node.js
Python
Ruby

// Express.js example — runs on YOUR backend (e.g. https://api.yourapp.com)
const express = require('express');
const app = express();

app.post('/api/health/connect', authenticateUser, async (req, res) => {
  try {
    const owUserId = req.user.openWearablesUserId;
    
    // Call Open Wearables API to generate a user-scoped token
    const response = await fetch(
      `${process.env.OPENWEARABLES_HOST}/api/v1/users/${owUserId}/token`,
      {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          app_id: process.env.OPENWEARABLES_APP_ID,
          app_secret: process.env.OPENWEARABLES_APP_SECRET,
        }),
      }
    );
    
    if (!response.ok) {
      throw new Error('Failed to generate token');
    }
    
    const { access_token, refresh_token } = await response.json();
    
    // Return tokens to the mobile app (NOT the app credentials!)
    res.json({ 
      userId: owUserId, 
      accessToken: access_token,
      refreshToken: refresh_token,
    });
  } catch (error) {
    console.error('Health connect error:', error);
    res.status(500).json({ error: 'Failed to connect health' });
  }
});

# FastAPI example — runs on YOUR backend (e.g. https://api.yourapp.com)
from fastapi import FastAPI, Depends, HTTPException
import httpx
import os

app = FastAPI()

@app.post("/api/health/connect")
async def connect_health(current_user = Depends(get_current_user)):
    ow_user_id = current_user.open_wearables_user_id

    # Call Open Wearables API to generate a user-scoped token
    async with httpx.AsyncClient() as client:
        response = await client.post(
            f"{os.environ['OPENWEARABLES_HOST']}/api/v1/users/{ow_user_id}/token",
            json={
                "app_id": os.environ["OPENWEARABLES_APP_ID"],
                "app_secret": os.environ["OPENWEARABLES_APP_SECRET"],
            },
        )
        
        if response.status_code != 200:
            raise HTTPException(500, "Failed to generate token")
        
        data = response.json()
    
    # Return tokens to the mobile app
    return {
        "userId": str(ow_user_id),
        "accessToken": data["access_token"],
        "refreshToken": data["refresh_token"],
    }

# Rails controller example — runs on YOUR backend (e.g. https://api.yourapp.com)
class HealthController < ApplicationController
  before_action :authenticate_user!

  def connect
    ow_user_id = current_user.open_wearables_user_id

    # Call Open Wearables API to generate a user-scoped token
    response = HTTParty.post(
      "#{ENV['OPENWEARABLES_HOST']}/api/v1/users/#{ow_user_id}/token",
      headers: { 'Content-Type' => 'application/json' },
      body: {
        app_id: ENV['OPENWEARABLES_APP_ID'],
        app_secret: ENV['OPENWEARABLES_APP_SECRET']
      }.to_json
    )

    if response.success?
      # Return tokens to the mobile app
      render json: {
        userId: ow_user_id,
        accessToken: response['access_token'],
        refreshToken: response['refresh_token']
      }
    else
      render json: { error: 'Failed to connect' }, status: 500
    end
  end
end

The user_id in the URL is the Open Wearables User ID (UUID). You should store this mapping in your database when you first Create User via the Open Wearables API.

Step 2: SDK Initialization & Configuration

Initialize the SDK once in your Application class or main activity, then configure it with your backend host.

import com.openwearables.health.sdk.OpenWearablesHealthSDK

class MyApplication : Application() {

    override fun onCreate() {
        super.onCreate()

        // Initialize SDK (once per app lifecycle)
        val sdk = OpenWearablesHealthSDK.initialize(this)

        // Optional: Set up logging
        sdk.logListener = { message ->
            Log.d("HealthSDK", message)
        }

        // Optional: Set log level (default is OWLogLevel.DEBUG — logs only in debuggable builds)
        sdk.logLevel = OWLogLevel.ALWAYS

        // Optional: Handle auth errors (e.g. token expired)
        sdk.authErrorListener = { error ->
            Log.e("HealthSDK", "Auth error: $error")
        }

        // Configure with your backend host
        sdk.configure(host = "https://api.openwearables.io")
    }
}

Configuration Options

Parameter	Type	Description
`host`	`String`	Required. The Open Wearables API base URL (host only, without path suffix)

Provide only the base host URL, e.g. https://your-domain.com. Do not append /api/v1/ or any other path — the SDK adds the required path prefix automatically.

// For self-hosted Open Wearables
sdk.configure(host = "https://your-domain.com")

Session Restoration

The SDK automatically restores credentials from EncryptedSharedPreferences:

val sdk = OpenWearablesHealthSDK.getInstance()

if (sdk.isSessionValid()) {
    val userId = sdk.restoreSession()
    Log.d("HealthSDK", "Session restored for user: $userId")
} else {
    // Need to sign in
}

After getting credentials from your backend, sign in with the SDK.

The userId parameter is the Open Wearables User ID (UUID) — the id returned by the Create User endpoint. Do not pass your own external_user_id here.

Token-Based Authentication (Recommended)

suspend fun connectHealth(credentials: HealthCredentials) {
    val sdk = OpenWearablesHealthSDK.getInstance()

    sdk.signIn(
        userId = credentials.userId,
        accessToken = credentials.accessToken,
        refreshToken = credentials.refreshToken,
        apiKey = null
    )

    Log.d("HealthSDK", "Signed in: ${credentials.userId}")
}

API Key Authentication

For simpler setups (e.g. internal tools):

sdk.signIn(
    userId = "user123",
    accessToken = null,
    refreshToken = null,
    apiKey = "your_api_key"
)

API key authentication embeds the key in the app. Only use this for internal or trusted applications. For production apps, always use token-based authentication.

Automatic Token Refresh

When you provide a refreshToken, the SDK automatically handles 401 responses by refreshing the access token and retrying the request. You can also update tokens manually:

sdk.updateTokens(
    accessToken = newAccessToken,
    refreshToken = newRefreshToken
)

Step 4: Select Health Provider

Before requesting permissions, you must select a health data provider:

val sdk = OpenWearablesHealthSDK.getInstance()

// Check available providers
val providers = sdk.getAvailableProviders()
for (p in providers) {
    Log.d("HealthSDK", "${p["displayName"]} (${p["id"]}) - available: ${p["isAvailable"]}")
}

// Set the provider based on user selection or your default
val success = sdk.setProvider("google") // or "samsung" for Samsung Health
if (!success) {
    Log.e("HealthSDK", "Selected provider is unavailable on this device")
}

Call setProvider() before requestAuthorization(). The SDK needs to know which provider to request permissions from.

Provider Comparison

Feature	Health Connect (`"google"`)	Samsung Health (`"samsung"`)
Device support	All Android 10+	Samsung devices only
Data types	25+ types	16 types
Pre-installed	Android 14+	Samsung devices
Install required	Play Store (Android < 14)	Samsung Health app

Health Connect is recommended as the default provider for the widest device and data type support.

Step 5: Request Permissions

Request access to specific health data types. The type IDs are string-based:

suspend fun requestHealthPermissions(): Boolean {
    val sdk = OpenWearablesHealthSDK.getInstance()

    val authorized = sdk.requestAuthorization(
        types = listOf(
            "steps",
            "heartRate",
            "restingHeartRate",
            "sleep",
            "workout",
            "activeEnergy",
            "bodyMass"
        )
    )

    if (authorized) {
        Log.d("HealthSDK", "Health permissions granted")
    } else {
        Log.d("HealthSDK", "Some permissions were denied")
    }

    return authorized
}

Make sure to call setActivity() on the SDK before requesting authorization, so the SDK can launch the permission dialog from the correct Activity context.

Step 6: Start Background Sync

Enable background sync to keep data flowing even when your app is in the background:

suspend fun startSync() {
    val sdk = OpenWearablesHealthSDK.getInstance()
    sdk.startBackgroundSync()
    Log.d("HealthSDK", "Background sync started: ${sdk.isSyncActive()}")
}

Controlling Sync History Depth

By default, the SDK syncs all available historical data on the first sync. Use the syncDaysBack parameter to limit how far back the sync goes:

// Sync only the last 90 days of data
sdk.startBackgroundSync(syncDaysBack = 90)

// Sync last 30 days
sdk.startBackgroundSync(syncDaysBack = 30)

// Full sync — all available history (default)
sdk.startBackgroundSync()

Parameter	Type	Default	Description
`syncDaysBack`	`Int?`	`null`	Number of days of historical data to sync. Syncs from the start of the day that many days ago. When `null`, syncs all available history. The value is persisted and used for subsequent background syncs until changed.

Background Sync Behavior

Mechanism	Description
WorkManager	Periodic background sync with system-managed scheduling
Foreground Service	Used during active sync for reliability (`dataSync` type)
Notification	Shows a notification during active sync (Android 13+ requires permission)

Manual Sync

Trigger an immediate sync:

sdk.syncNow()

Stop Sync

sdk.stopBackgroundSync()

Log Level

Control SDK log output using the logLevel property. By default, the SDK uses OWLogLevel.DEBUG, which outputs logs only in debuggable builds:

val sdk = OpenWearablesHealthSDK.getInstance()

// Always show logs (including release builds)
sdk.logLevel = OWLogLevel.ALWAYS

// Only show logs in debuggable builds (default)
sdk.logLevel = OWLogLevel.DEBUG

// Disable all logs
sdk.logLevel = OWLogLevel.NONE

Level	Description
`OWLogLevel.NONE`	No logs at all
`OWLogLevel.ALWAYS`	Logs are always emitted (Logcat + listener) regardless of build type
`OWLogLevel.DEBUG`	Logs are emitted only in debuggable builds (default)

Set OWLogLevel.ALWAYS during development or when troubleshooting sync issues in production. Switch to OWLogLevel.NONE if you want to suppress all SDK output.

Lifecycle Management

Notify the SDK of app lifecycle changes for optimal sync behavior:

class MainActivity : AppCompatActivity() {

    override fun onResume() {
        super.onResume()
        OpenWearablesHealthSDK.getInstance().onForeground()
    }

    override fun onPause() {
        super.onPause()
        OpenWearablesHealthSDK.getInstance().onBackground()
    }
}

Complete Integration Example

Here’s a complete ViewModel showing the full integration:

import androidx.lifecycle.ViewModel
import androidx.lifecycle.viewModelScope
import com.openwearables.health.sdk.OpenWearablesHealthSDK
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.StateFlow
import kotlinx.coroutines.launch

class HealthViewModel : ViewModel() {

    private val sdk = OpenWearablesHealthSDK.getInstance()

    private val _isConnected = MutableStateFlow(false)
    val isConnected: StateFlow<Boolean> = _isConnected

    private val _isSyncing = MutableStateFlow(false)
    val isSyncing: StateFlow<Boolean> = _isSyncing

    init {
        _isConnected.value = sdk.isSessionValid()
        _isSyncing.value = sdk.isSyncActive()
    }

    fun connect(userId: String, accessToken: String, refreshToken: String?) {
        viewModelScope.launch {
            try {
                // Sign in
                sdk.signIn(
                    userId = userId,
                    accessToken = accessToken,
                    refreshToken = refreshToken,
                    apiKey = null
                )

                // Set provider
                sdk.setProvider("google")

                // Request permissions
                val authorized = sdk.requestAuthorization(
                    types = listOf(
                        "steps", "heartRate", "sleep",
                        "workout", "activeEnergy"
                    )
                )

                if (authorized) {
                    sdk.startBackgroundSync(syncDaysBack = 90)
                }
            } catch (e: Exception) {
                Log.e("HealthSDK", "Connection failed", e)
            }
        }
    }

    fun disconnect() {
        viewModelScope.launch {
            sdk.stopBackgroundSync()
            sdk.signOut()
            _isConnected.value = false
            _isSyncing.value = false
        }
    }

    fun syncNow() {
        viewModelScope.launch {
            sdk.syncNow()
        }
    }

    fun checkAndResumeSync() {
        viewModelScope.launch {
            if (sdk.hasResumableSyncSession()) {
                val status = sdk.getSyncStatus()
                Log.d("HealthSDK", "Resuming sync, sent: ${status["sentCount"]}")
                sdk.resumeSync()
            }
        }
    }

    fun resyncAllData() {
        viewModelScope.launch {
            sdk.resetAnchors()
            sdk.syncNow()
        }
    }

    override fun onCleared() {
        super.onCleared()
        sdk.destroy()
    }
}

Using the ViewModel

class HealthActivity : AppCompatActivity() {

    private val viewModel: HealthViewModel by viewModels()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val sdk = OpenWearablesHealthSDK.getInstance()
        sdk.setActivity(this)

        // Observe state
        lifecycleScope.launch {
            viewModel.isConnected.collect { connected ->
                updateUI(connected)
            }
        }

        // Check for interrupted syncs
        viewModel.checkAndResumeSync()

        connectButton.setOnClickListener {
            val credentials = getCredentialsFromBackend()
            viewModel.connect(
                userId = credentials.userId,
                accessToken = credentials.accessToken,
                refreshToken = credentials.refreshToken
            )
        }

        disconnectButton.setOnClickListener {
            viewModel.disconnect()
        }

        syncNowButton.setOnClickListener {
            viewModel.syncNow()
        }
    }

    override fun onDestroy() {
        super.onDestroy()
        OpenWearablesHealthSDK.getInstance().setActivity(null)
    }
}

Data Sync Endpoint

The SDK sends health data to:

POST {host}/api/v1/sdk/users/{userId}/sync

The payload includes a provider field ("samsung" or "google") and the SDK version:

{
  "provider": "google",
  "sdkVersion": "0.5.0",
  "syncTimestamp": "2025-01-15T10:30:00Z",
  "data": {
    "records": [...],
    "workouts": [...],
    "sleep": [...]
  }
}

Data is automatically normalized to the Open Wearables unified data model and can be accessed through the standard API endpoints.

Getting started

Architecture

Providers

Open Wearables Mobile App

Sync SDK

MCP Server

Developer Guides

Configuration

Deployment

Support

Android Health Connect Integration Guide | Open Wearables

Overview

Authentication Architecture

Step 1: Backend Setup

Generate Access Token

Step 2: SDK Initialization & Configuration

Configuration Options

Session Restoration

Token-Based Authentication (Recommended)

API Key Authentication

Automatic Token Refresh

Step 4: Select Health Provider

Provider Comparison

Step 5: Request Permissions

Step 6: Start Background Sync

Controlling Sync History Depth

Background Sync Behavior

Manual Sync

Stop Sync

Log Level

Lifecycle Management

Complete Integration Example

Using the ViewModel

Data Sync Endpoint

Next Steps

Troubleshooting

Data Types

Getting started

Architecture

Providers

Open Wearables Mobile App

Sync SDK

MCP Server

Developer Guides

Configuration

Deployment

Support

​Overview

​Authentication Architecture

​Step 1: Backend Setup

​Generate Access Token

​Step 2: SDK Initialization & Configuration

​Configuration Options

​Session Restoration

​Step 3: Sign In

​Token-Based Authentication (Recommended)

​API Key Authentication

​Automatic Token Refresh

​Step 4: Select Health Provider

​Provider Comparison

​Step 5: Request Permissions

​Step 6: Start Background Sync

​Controlling Sync History Depth

​Background Sync Behavior

​Manual Sync

​Stop Sync

​Log Level

​Lifecycle Management

​Complete Integration Example

​Using the ViewModel

​Data Sync Endpoint

​Next Steps

Troubleshooting

Data Types

Overview

Authentication Architecture

Step 1: Backend Setup

Generate Access Token

Step 2: SDK Initialization & Configuration

Configuration Options

Session Restoration

Step 3: Sign In

Token-Based Authentication (Recommended)

API Key Authentication

Automatic Token Refresh

Step 4: Select Health Provider

Provider Comparison

Step 5: Request Permissions

Step 6: Start Background Sync

Controlling Sync History Depth

Background Sync Behavior

Manual Sync

Stop Sync

Log Level

Lifecycle Management

Complete Integration Example

Using the ViewModel

Data Sync Endpoint

Next Steps