Running Periodic Background Fetch in Expo with Task Manager

Insight

Expo’s TaskManager lets you define headless tasks that run even when the UI is not active. Pair it with expo-background-fetch to schedule periodic network syncs, ideal for push‑enabled news feeds or token refreshes. The system respects OS power policies, so you should keep the task lightweight and idempotent.

Example

import * as TaskManager from 'expo-task-manager';
import * as BackgroundFetch from 'expo-background-fetch';

const FETCH_TASK = 'background-fetch-sync';

TaskManager.defineTask(FETCH_TASK, async () => {
  try {
    const res = await fetch('https://api.example.com/sync');
    const data = await res.json();
    // store data locally, e.g., using MMKV or AsyncStorage
    return BackgroundFetch.Result.NewData;
  } catch {
    return BackgroundFetch.Result.Failed;
  }
});

await BackgroundFetch.registerTaskAsync(FETCH_TASK, {
  minimumInterval: 15 * 60, // 15 minutes
  stopOnTerminate: false,
  startOnBoot: true,
});

Takeaway

Schedule background fetches with a short interval and keep the work minimal; heavy processing should be deferred to when the app is foregrounded. This pattern ensures your app stays up‑to‑date without draining battery.