Implementing Reliable Background Location Tracking in Expo on Android

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Foreground Service.

Building apps that track user location in the background can be tricky—Android requires a persistent foreground service, special permissions, and a correctly wired-up native project. If you’re using Expo (managed or bare), here’s a step-by-step guide to get background location tracking running smoothly, including how to troubleshoot common Gradle errors around “No matching variant” for React Native modules.

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Why a Foreground Service?

Android 8.0+ enforces that any long-running background work needs a visible notification via a foreground service. For location apps, this means:

• User trust: they see an ongoing notification (“Tracking your location”)

• System compliance: avoids unexpected kills and MissingForegroundServiceTypeException

Expo’s expo-location + expo-task-manager packages leverage this under-the-hood via a native service—but if you eject (or prebuild to a bare workflow), you must make sure your Android manifest and Gradle setup include the right declarations.

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1. In a Managed Expo App

If you never eject, Expo Go handles all the native wiring. All you need is:

1. Install packages

    expo install expo-location expo-task-manager
   

2. Configure app.json

    {
      "expo": {
        // … other settings …
        "android": {
          "permissions": [
            "ACCESS_FINE_LOCATION",
            "ACCESS_COARSE_LOCATION",
            "FOREGROUND_SERVICE"
          ]
        },
        "plugins": [
          [
            "expo-location",
            {
              "foregroundService": {
                "notificationTitle": "Location Tracking Active",
                "notificationBody": "We’re recording your location in the background.",
                "notificationColor": "#FF0000"
              }
            }
          ]
        ]
      }
    }
   

3. Define & start your task

    // locationTask.js
    import * as TaskManager from 'expo-task-manager';
   
    export const LOCATION_TASK_NAME = 'BACKGROUND_LOCATION_TASK';
   
    TaskManager.defineTask(LOCATION_TASK_NAME, ({ data, error }) => {
      if (error) {
        console.error(error);
        return;
      }
      const { locations } = data;
      // Send locations to server or update your store…
    });
   

    // App.js
    import * as Location from 'expo-location';
    import { LOCATION_TASK_NAME } from './locationTask';
   
    async function startTracking() {
      const { status: fg } = await Location.requestForegroundPermissionsAsync();
      const { status: bg } = await Location.requestBackgroundPermissionsAsync();
      if (fg !== 'granted' || bg !== 'granted') {
        return Alert.alert('Permissions required');
      }
      await Location.startLocationUpdatesAsync(LOCATION_TASK_NAME, {
        accuracy: Location.Accuracy.Highest,
        timeInterval: 5_000,
        distanceInterval: 10,
        showsBackgroundLocationIndicator: true,
        foregroundService: {
          notificationTitle: 'Tracking your location',
          notificationBody: 'Tap to return to the app',
        },
      });
    }
   

4. Rebuild on a real device

    # Expo Go won’t run background tasks—use a dev client or standalone:
    eas build --profile development --platform android
   

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2. Ejecting / Bare Workflow: Getting Your AndroidManifest Right

Once you run expo prebuild, Expo generates an android/ folder—but does not merge future plugin updates. You must manually confirm:

1. Permissions before <application>

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION"/>
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_LOCATION"/>
   

2. Service declaration inside <application>

    <application …>
      <!-- Expo Location background-task service -->
      <service
        android:name="expo.modules.location.tasks.LocationTaskService"
        android:exported="false"
        android:foregroundServiceType="location" />
      …  
    </application>
   

3. Clean & rebuild

    cd android
    ./gradlew clean
    cd ..
    eas build --platform android --profile production
   

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3. Troubleshooting “No matching variant” Gradle Errors

If your build fails during :app:assembleRelease with messages like:

Could not resolve project :react-native-async-storage_async-storage. No matching variant of project … was found.

…that means your native Gradle setup doesn’t know about those React Native modules. You have two paths:

A) Regenerate Android via Expo

If you’ve made no further custom edits (or can re-apply them):

# From your project root:
rm -rf android
expo prebuild --clean
eas build --platform android --profile production

Expo will autolink all modules (AsyncStorage, DateTimePicker, Maps, Reanimated, etc.) into settings.gradle and build.gradle.

B) Manually Link Modules in settings.gradle

If you need to preserve custom native code, open android/settings.gradle and below include ':app' add lines like:

include ':react-native-async-storage_async-storage'
project(':react-native-async-storage_async-storage').projectDir = new File(rootProject.projectDir, '../node_modules/@react-native-async-storage/async-storage/android')

include ':react-native-community_datetimepicker'
project(':react-native-community_datetimepicker').projectDir = new File(rootProject.projectDir, '../node_modules/@react-native-community/datetimepicker/android')

…repeat for each missing module…

Then:

cd android
./gradlew clean
cd ..
eas build --platform android --profile production

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4. Wrapping Up

By combining Expo’s plugin-driven approach with a correctly configured AndroidManifest and (if needed) manual Gradle linking, you’ll have:

• A robust foreground service that keeps your location task running

• All necessary Android permissions, especially FOREGROUND_SERVICE_LOCATION on Android 13+

• Proper linkage of community modules in your bare workflow

With this setup, your users will see a consistent notification, Android will honor your background work, and your EAS builds will complete without XML or variant-matching errors. Happy coding!