Runtime version

Choosing the policy is a team decision. appVersion is simple but relies on the discipline of bumping version at every release that includes native changes; one forgotten bump and an update breaks production builds. fingerprint removes that risk by hashing whatever touches native code (native folders, config, native dependencies); since SDK 58, the default balanced preset ignores version bumps and hashes native modules by name and version, which cuts needless rebuilds. It still yields more runtime versions than a manual policy, so more builds to keep alive in parallel. A manual string suits projects that already follow a strict release process.

To check what a build embeds, eas build:list shows each build’s runtime version, and eas update:list each update’s; the two must match for the platform concerned. eas fingerprint:compare explains why two fingerprints differ, which avoids the “but I changed nothing native” conversation when a dependency updated a podspec. The Updates.runtimeVersion API gives the value at runtime, useful in an internal debug screen.

The most expensive pitfall: projects that keep runtimeVersion frozen at "1.0.0" for months “so updates reach everyone”. Sooner or later an update references a native module the old builds lack, and the crash hits precisely the users who never update their app.