Android Developer Interview Questions UK: 8 Real Questions and What Interviewers Want

Before your Android Developer interview, it helps to see the questions from the interviewer's side. We have picked eight from our set of 16 and added the reason each one gets asked.

Eight Android Developer interview questions, and what the interviewer is thinking

1. Can you explain the Android activity and fragment lifecycle, and how you handle configuration changes such as screen rotation?

Why they ask: Lifecycle handling is the most fundamental Android knowledge and a common source of bugs.

2. What are the advantages of Jetpack Compose over the XML view system, and how do state and recomposition work?

Why they ask: Compose is now the standard for new Android UI, so they expect practical understanding.

3. How do Kotlin coroutines and Flow work, and how do you use them for asynchronous work in an Android app?

Why they ask: Asynchronous code is central to Android, and misuse causes crashes and leaks.

4. How would you structure an Android app architecturally? Explain MVVM, the role of repositories and where dependency injection fits.

Why they ask: Architecture knowledge shows whether you can build maintainable, testable apps.

5. How do you persist data locally in Android, and when would you use Room, DataStore or SharedPreferences?

Why they ask: They want to know you pick storage mechanisms appropriately.

6. Crash reports show a spike in crashes after your latest release, affecting around five per cent of users. What do you do?

Why they ask: They want to see calm, structured incident handling in production.

7. Tell me about a time you improved the stability or performance of an Android app.

Why they ask: They want evidence of measurable engineering impact.

8. Why do you want to be an Android developer, and how do you stay up to date with the platform?

Why they ask: They want to gauge genuine enthusiasm and continuing learning in a fast-moving field.

A sample answer to question 1

Can you explain the Android activity and fragment lifecycle, and how you handle configuration changes such as screen rotation?

An activity moves through onCreate, onStart and onResume when it becomes interactive, and back through onPause, onStop and onDestroy as it leaves. Fragments have an additional view lifecycle, with onCreateView and onDestroyView, which is a frequent source of memory leaks if you hold view references too long. On a configuration change such as rotation, the system destroys and recreates the activity by default. I avoid manually handling this and instead keep UI state in a ViewModel, which survives configuration changes, and use SavedStateHandle or rememberSaveable for state that must survive process death. I collect Flows in a lifecycle-aware way with repeatOnLifecycle or collectAsStateWithLifecycle so work stops when the screen isn't visible. I avoid long-lived references to contexts or views inside ViewModels. Testing with the Don't Keep Activities developer option and rotating mid-flow is a quick way to catch mistakes.

Common mistake to avoid: Overriding configChanges everywhere; Holding Context in a ViewModel

Want the rest?

Full model answers, key points and common mistakes for all 16 questions are on the Android Developer interview questions page. The first five are free, no sign-up needed.