Expo

Expo is a platform and set of tools built around React Native that lets developers build, build-and-ship, and update iOS and Android apps from a single JavaScript and TypeScript codebase, handling much of the native build tooling complexity that has historically made React Native development harder than it needs to be for teams without deep native mobile expertise. Its managed workflow provides a large library of pre-built native modules for common functionality like camera access, push notifications, and in-app purchases, letting developers add these features without writing custom native code in Swift or Kotlin, while still allowing teams to eject into custom native code when a project's needs genuinely require it. Expo Application Services handles cloud builds and app store submissions, meaning a developer doesn't need a Mac with Xcode installed locally just to produce an iOS build, which removes a significant infrastructure hurdle particularly for smaller teams or solo developers. Its over-the-air update feature, EAS Update, lets teams push JavaScript code changes directly to users' installed apps without going through a full app store review cycle, which is valuable for shipping bug fixes and minor updates quickly, though any change touching native code still requires a standard app store release. Expo is used broadly by startups and independent developers building cross-platform mobile apps who want React Native's productivity without owning the full native build and tooling complexity themselves.