Expo
The open-source framework React Native was missing: one codebase for iOS, Android and web, with navigation, permissions, camera, notifications and over-the-air updates already wired. Around it sits a paid service, EAS, which compiles your binaries and ships your updates without you building a pipeline.
Strengths
- Recommended by the official React Native documentation for any new app: this is not a side-ecosystem choice, it is the default path.
- One codebase for iOS, Android and web. For a product team without three mobile developers, that is the difference between shipping and not shipping.
- Over-the-air updates push a JavaScript fix without going back through store review.
- You see the app running on your own phone before installing a single native tool.
Limitations
- The framework is free, the build and distribution chain is not. The real cost of mobile arrives through EAS, not through the license.
- A native library with no compatible module is still a library you have to wrap yourself.
- SDK upgrades are frequent and follow React Native. An app left untouched for two years is painful to catch up.
Best for
- A web product team that has to ship a mobile app without hiring two native specialists.
- A prototype to put in a real user's hands this week, on their real phone.
- An app that shares its business logic with a site already written in React.