Our inspection app is used by technicians who walk through plant rooms, basements and underground car parks. For two years it was a normal online form: fill it in, press save, hope for signal. The support queue had a steady stream of "I pressed save and it vanished", and the honest answer was that the request had timed out and the React state was gone when the user navigated away. We rebuilt the write path so the device is the first place data lands and the server is the second. This p...