Over-the-Air (OTA) Updates definition
Over-the-air (OTA) updates are software updates delivered wirelessly to devices already in use, without a cable or manual reinstall. In mobile apps the term usually means pushing JavaScript and asset changes to React Native or similar apps without a new app store release. It also covers firmware updates for phones, cars and IoT devices.
How do OTA updates work in mobile apps?
A React Native or hybrid app has two parts: a compiled native binary that goes through app store review, and a bundle of JavaScript and assets that the binary loads at startup. An OTA service hosts new bundles, grouped by release channel and by the native runtime version they are compatible with. The app checks for an update on launch, downloads it in the background and applies it on the next start or immediately.
Expo's EAS Update is the most widely used service for React Native, and Microsoft's App Center CodePush was retired in 2025, moving many teams to EAS Update or self-hosted alternatives. Capacitor apps use live update services, and Shorebird offers code push for Flutter. Changes to native code, permissions or SDK versions still require a full store release.
App store rules for OTA updates
Apple and Google both allow apps to download interpreted code such as JavaScript, provided updates do not change the app's primary purpose, add features that would have needed review, or bypass store security and payment rules. In practice OTA is accepted for bug fixes, content and copy changes, and small improvements, while major new features should ship through a normal release so reviewers see them.
Benefits of OTA updates
- Critical bug fixes reach users in hours instead of waiting for review and manual updates.
- More users run the latest version, since no store update is needed.
- Staged rollouts send an update to a small percentage of users first.
- Instant rollback to a previous bundle if something goes wrong.
- Faster experiments with copy, layout and configuration.
Risks and best practices
The biggest risk is shipping a JavaScript bundle that calls native code the installed binary does not contain, which crashes the app on launch. Runtime version policies prevent this by delivering each bundle only to compatible binaries. Because OTA skips store review, your own quality gates matter more: the same tests, code review and staged rollout you would use for a store release.
- Tie every bundle to a runtime or native version.
- Roll out gradually and watch crash and error rates before expanding.
- Sign bundles so devices only accept updates from your servers.
- Keep a tested rollback path and a launch fallback to the embedded bundle.
- Never use OTA to ship features that would fail store review.
OTA firmware updates for devices
Outside apps, OTA updates deliver operating system and firmware upgrades to phones, cars, routers and IoT devices. Reliable designs use A/B partitions, so the device installs the update to an inactive slot and switches only after it boots successfully, with signed images and resumable downloads over weak connections. Vehicle makers must also meet regulations such as UN R156 on software update management. Nexzem builds OTA pipelines for both React Native apps and connected devices, with staged rollouts and rollback built in.