OTA Update Model

EAS Update ships compatible JavaScript and assets to installed app binaries.

Safe OTA Changes

Usually safe	Requires caution
Copy changes	Route behavior with native deep-link assumptions
JavaScript bug fixes	Large asset changes
Layout and style changes	Feature flags that expose hidden native assumptions
API endpoint logic	Changes depending on new native module behavior
Images and static assets	Platform-specific behavior that was not device-tested

Not OTA-Safe

Native code.
Native dependencies.
Expo SDK upgrades.
Android permissions.
iOS usage descriptions or background modes.
App package name or bundle identifier.
Icons and splash config that affect native projects.
Runtime-incompatible JavaScript.
Store policy or privacy behavior that needs review.

Runtime Version

Runtime version is the compatibility label between a binary and an update. A binary only receives updates with a compatible runtime version.

Common policies:

Policy	Use when
`appVersion`	Solo-dev apps that bump app version for native releases
`fingerprint`	You want automatic runtime changes when native inputs change
Custom	You need manual cross-platform control and can maintain discipline

Default to appVersion for simple solo-dev apps unless the project has frequent native changes or strong reasons to use fingerprint.

Rollout Flow

eas update --branch preview --message "Smoke update"
# install/open compatible preview build and verify
eas update --branch production --message "Production hotfix"
# if bad
eas update:rollback

Warning: Store rules still apply to OTA updates. Do not use OTA to sneak around review for sensitive permissions, payment behavior, privacy changes, or platform policy.