Building Apps Faster: How AI and React Native are Changing the Game – Charlie Cheever, Expo

Expo Go is a free App Store app with most Expo SDK modules built in. AI app builders (Bolt, Replit, Lovable, v0) pop up a QR code; the user downloads Expo Go, scans it and has the generated app live on their phone in 30-40 seconds, with changes appearing as they prompt. Expo then offers npm testflight and cloud builds to take the app to TestFlight and the App Store.

Bluesky had a 10-person team with no iOS or Android developers and a tight timeline. One engineer (Paul), with no prior React experience, learned it on the fly and built the first version of the app for iOS, Android and web with Expo in four months.

Many Expo customers had working, well-reviewed Swift/Objective-C iOS apps and Java/Kotlin Android apps but could not add features fast enough, struggled to keep platforms in sync, struggled to hire specialists, and were at risk if their one Android or iOS developer left. They rewrote into one React codebase, staffed it from the same pool as web developers, and got web-style instant reloads instead of recompiling. They drop into native Swift/Kotlin modules only where needed.

The Expo framework and SDK are open source and free. Expo makes money from cloud services: running Xcode and Android Studio builds in the cloud, over-the-air updates (the analog of web hosting), web hosting, automatic submission to TestFlight/App Store and scripted tests on build artifacts.

Because Expo is open source, it does not know everyone who uses it. The team ran a research project that downloaded the top 100 apps in every App Store category and inspected them to see which were built with Expo.

Expo released an npm testflight command: run it in an Expo project and it walks the user through every step to put the app in TestFlight, so they never deal with provisioning profiles or distribution certificates. Aimed at vibe coders and developers stuck on the last mile to the App Store.

Bolt and Lovable both made Supabase the standard back end, connecting accounts for users and likely adding system-prompt rules such as 'use Supabase' and 'don't leak the private key into the client', keeping generated code on well-trained rails.