2025 Edition · English
30-Day Android Interview Challenge
Thirty in-depth carousels that take you from the Activity lifecycle to system design. Each day answers interview questions at four levels — Junior, Mid, Senior and Architect — with code and real-world examples.
The 2026 edition — rebuilt from your feedback, in English and Persian — is being published on LinkedIn right now.Follow on LinkedIn
Days 1–8Foundations
Day 1 · 64 slidesAndroid Fundamentals & Activity Lifecycle
Day 2 · 51 slidesFragments & the Fragment Lifecycle
Day 3 · 87 slidesArchitecture Patterns: MVC, MVP, MVVM, MVI
Day 4 · 104 slidesKotlin Coroutines & Concurrency
Day 5 · 85 slidesKotlin Flow & Reactive Programming
Day 6 · 86 slidesJetpack Components: ViewModel, LiveData, Room
Day 7 · 86 slidesDependency Injection: Dagger & Hilt
Day 8 · 84 slidesJetpack Compose FundamentalsDays 9–16Testing, networking & data
Day 9 · 58 slidesTesting Strategies — Part 1
Day 10 · 44 slidesTesting Strategies — Part 2
Day 11 · 49 slidesNetwork Layer: Retrofit, OkHttp & Security — Part 1
Day 12 · 59 slidesNetwork Layer: Retrofit, OkHttp & Security — Part 2
Day 13 · 43 slidesData Layer Architecture — Part 1
Day 14 · 77 slidesData Layer Architecture — Part 2
Day 15 · 50 slidesBackground Processing: WorkManager & Services — Part 1
Day 16 · 64 slidesBackground Processing: WorkManager & Services — Part 2Days 17–24Performance, security & delivery
Day 17 · 46 slidesPerformance Optimization & Profiling — Part 1
Day 18 · 54 slidesPerformance Optimization & Profiling — Part 2
Day 19 · 39 slidesSecurity Best Practices — Part 1
Day 20 · 45 slidesSecurity Best Practices — Part 2
Day 21 · 25 slidesBuild System & Gradle Optimization — Part 1
Day 22 · 35 slidesBuild System & Gradle Optimization — Part 2
Day 23 · 33 slidesCI/CD Pipeline & DevOps — Part 1
Day 24 · 33 slidesCI/CD Pipeline & DevOps — Part 2
