Zero‑Downtime OTA Updates with Expo Updates and EAS

Insight

Expo's expo-updates module lets you push JavaScript and asset changes without a store release. When paired with EAS Build and EAS Update, you can ship a new bundle, let the client download it in the background, and apply it on the next foreground launch – all without disrupting the current session. The key is to enable fallbackToCacheTimeout and trigger a silent reload only when the new bundle is ready.

Example

// app.json (or eas.json) – enable OTA
{
  "expo": {
    "updates": {
      "fallbackToCacheTimeout": 0,
      "url": "https://u.expo.dev/<PROJECT_ID>"
    }
  }
}

// Somewhere in your root component
import * as Updates from 'expo-updates';
import { useEffect } from 'react';

useEffect(() => {
  const check = async () => {
    const { isAvailable } = await Updates.checkForUpdateAsync();
    if (isAvailable) {
      await Updates.fetchUpdateAsync();
      await Updates.reloadAsync(); // applies silently on next render
    }
  };
  check();
}, []);

Takeaway

Configure fallbackToCacheTimeout to 0 so the app never stalls waiting for a remote bundle, and let expo-updates handle the download silently. This pattern gives you zero‑downtime releases, ideal for hot‑fixes and feature flags, while keeping the user experience seamless.