Test a no-code app by walking every screen in its empty state, pressing back from everywhere, refusing every permission once, turning off the network, rotating the phone, and doing it all again on the release build rather than the preview. This finds the great majority of problems that reach users. Each item below takes a minute or two.
The checklist
1. Empty states
Fresh install, no data. Does every list say something helpful ("No bookings yet — tap + to add one") rather than showing a blank screen? Does the Stats screen cope with zero entries?
2. Back button
From every screen, press the system back button (or gesture). It should go to the previous screen, never close the app unexpectedly, never loop. On the first tab, back should exit.
3. Permissions refused
Ask for the camera, location, notifications — and tap Don't allow. The app should explain and continue, not crash or freeze. Then allow it in system settings and confirm the feature works without a restart.
4. Offline
Airplane mode. Content loaded from a sheet should show the cached copy with a quiet "offline" notice. Forms should tell you they cannot send, not pretend they did.
5. Rotation and small screens
Rotate to landscape on every screen. Try the smallest phone you can borrow. Text should not overflow; buttons should stay reachable.
6. Long text
A product named "Extra Large Hand-Poured Soy Candle with Sandalwood and Vanilla" — does the card wrap or clip sensibly?
7. Dark mode
If the phone is in dark mode, is everything readable? If the app has its own theme, does it override consistently?
8. Forms
Submit empty. Submit with nonsense in the phone field. Submit twice quickly. Each should be handled with a message, not a duplicate or a crash.
9. Notifications
Set a reminder for two minutes from now, lock the phone, wait. Tap the notification — it should open the right screen.
10. Release build
The preview in the builder and the debug build are forgiving. Install the signed release bundle or APK on a phone that has never had the app and repeat items 1–4. This is what reviewers and users get.
Reporting what you find
Back in the builder, one bug per message: what you did, what you expected, what happened, on which screen. "On Stats with no habits, the screen is blank. Show a message and a button to add a habit." The iteration guide covers phrasing.
Borrow two phones
Your phone is one data point. A cheap Android and a large one, ideally on different Android versions, catch layout and permission differences that no amount of testing on one device will. Family members are a free QA team and a surprisingly honest one.