
Not every user has perfect internet. Apps must behave well even without network access and QA needs to test that.
Why it matters:
- Mobile apps often break silently when losing internet.
- Offline behavior exposes hidden errors in caching, state management, and API handling.
- It improves real-world reliability (subways, elevators, rural areas, airports).
How to test:
- Turn on Airplane Mode in the device.
- Disable WiFi/data during key actions (login, checkout, form submission).
- Observe if the app:
- Shows a clear offline message
- Prevents risky actions
- Saves data locally
- Syncs correctly once connection returns.
- Check logs to confirm offline requests aren’t failing silently.
Real Example:
In a mobile app, filling a form offline should store the data locally. But some apps crash or lose the form entirely when connectivity drops. Testing offline exposes this immediately.
Pro Tip:
If an app can’t survive 10 seconds without internet, users won’t survive using it.