Underneath every phone app is a platform it borrows from — the runtime, the navigation, the camera and file access, the pieces that talk to iOS and Android. Ours moved this week, by four major versions, to the current React Native and Expo release. If you open the app and see nothing different, that is the result we wanted.
Why move at all
A platform you stop updating becomes a platform you cannot update. Each release the operating systems add requirements, the security patches land on the newest line first, and the gap between what you run and what is supported grows until closing it is a rewrite. Four versions in one step was already further than we like. Moving in one careful piece, with a full test drive on the other side, is cheaper than moving later.
What the drive found
The scripted test that walks the whole app on a device caught one real regression before any person did. Android now draws apps edge to edge by default, and the tab bar at the bottom of the screen was sizing itself as if the gesture strip did not exist — so each tab's label rendered just below its button, visible and untappable. Four of sixteen checks failed; the fix was a few lines; sixteen of sixteen passed after. That bar is the first thing we will ask about if anything ever looks off on an iPhone, too.
See what you are running
Open More and scroll to About. It shows the app version — a date, so you can tell at a glance how old it is — and which over-the-air update is currently running. Fixes now reach installed phones on the launch after we publish them, without an app-store cycle, and this week's build was the first on the new platform to receive one. We watched it arrive on an iPhone and on Android before writing this.
The best platform upgrade is the one you only find out about by reading this.