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How to prepare for an Android interview (a 4-week plan)

A focused, week-by-week plan to go from rusty to ready for an Android engineering interview without burning out.

Most Android interview prep fails for one reason: it’s unfocused. You bookmark forty articles, grind random LeetCode, and still walk in unsure. Here’s a tighter plan that maps to what Android interviews actually test.

Week 1 - Language & concurrency

This is where the most points are won and lost. Spend the week on:

  • Kotlin fundamentals: null safety, data/sealed classes, scope functions, generics.
  • Coroutines & Flow: structured concurrency, launch vs async, dispatchers, cancellation, StateFlow vs SharedFlow.

Don’t just read - write small snippets and explain them out loud. If you can’t teach it, you don’t know it yet. Drill the Coroutines topic.

Week 2 - Android framework & Compose

  • Lifecycles, configuration changes, process death, and why the ViewModel exists.
  • Jetpack Compose: recomposition, state hoisting, side-effect APIs, and performance.

Build one tiny app from scratch this week. Nothing teaches the framework like fighting it.

Week 3 - Architecture & system design

  • MVVM vs MVI, unidirectional data flow, repository pattern, DI with Hilt.
  • Practice two or three mobile system design prompts out loud: an image feed, a chat app, an offline-first client. Always name the trade-offs.

Week 4 - Mock interviews and stories

  • Do timed mock interviews, ideally with another engineer.
  • Prepare three behavioural stories with concrete impact (“I cut cold start by 30%”).
  • Review the interview experiences for companies on your list.

A few principles

Depth beats breadth. Interviewers can tell the difference between “I read about this” and “I’ve shipped this.”

  • Explain the why. Every answer should reach the trade-off, not stop at the definition.
  • Measure, don’t memorize. Mention the tools (Layout Inspector, profiler, recomposition counts) - it signals seniority.
  • Rest before the interview. A tired brain fumbles questions you actually know.

Good luck - and when you’re through it, pay it forward by sharing your own experience.