Top 30 Kotlin Interview Questions — From Basics to Coroutines
The 30 most commonly asked Kotlin interview questions with clear answers and code examples. Covers basics (val/var, null safety, string interpolation)...
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ANDROID 16 IS QUIET — BUT ONE OF THE MOST IMPORTANT RELEASES FOR DEVELOPERS
Android 16 (API level 36) is less about new UI features and more about making app behavior predictable and reliable. It introduces refinements in navi...
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Jetpack Compose Interview Questions — 25 Deep-Dive Questions for Senior Android Roles in 2026
If you're interviewing for a senior Android role in 2026, you're getting a Compose round. The questions that separate strong candidates from weak ones...
Compose Custom Layouts — From Layout {} to SubcomposeLayout, with Real Use Cases
Every Android developer hits the wall the same way. You need a row of size chips that wraps to the next line. Row doesn't wrap. FlowRow almost works b...
System Design — Design WhatsApp (The Walkthrough I'd Use in an Actual Interview)
The most common mistake in a system design interview is jumping straight to the architecture diagram. Candidates have seen "design WhatsApp" on a hund...
App Startup Optimization — Measure, Trim, and Ship Baseline Profiles
Cold start is the most ruthless metric in mobile. Users decide whether to keep your app in the first 1.5 seconds — yet I've seen apps take 4+ se...
Android Memory Leaks — The Five Patterns That Cause 90% of Them, and How to Fix Each
Three years ago I inherited a music app where memory climbed steadily during playback — 180MB after launch, 420MB after an hour, OOM crash after...
Top 50 Android Interview Questions — 2026 Edition (with the Follow-Ups They Actually Ask)
I've been on both sides of the Android interview table for over a decade. Questions have shifted hard since 2022 — view-based questions are out,...
Compose Animations — Picking the Right API and Avoiding the Recomposition Trap
The first Compose animation I shipped to production looked great in preview and catastrophic on a mid-range Samsung. Compose animations aren't hard be...
Testing Room Database — In-Memory Setup, DAO Tests, Migrations, Foreign Keys, and the Tests That Save Production
A Room migration that worked on my emulator and crashed for 12% of users is why I wrote this. Manual testing covers three scenarios; a 60-line test fi...
Testing Coroutines and Flows in Depth — runTest, TestDispatcher, Virtual Time, Turbine Patterns, and Production Recipes
Testing async code is hard — coroutines run on dispatchers, Flows emit over time, one missing advanceUntilIdle can silently skip half the test. ...
Compose UI Testing — Semantics, Finders, Assertions, Synchronization, and Production Patterns
The semantics tree is what tests see — not pixels. This complete guide covers Compose UI testing from zero to production: createComposeRule setu...
Unit Testing in Android — JUnit 5, MockK, Turbine, ViewModels, Flows, and Production Patterns
Unit tests catch bugs before users do. This guide walks through the core mindset, setup with JUnit 5, MockK, Turbine, and coroutines-test, and how to ...
MVVM — Unidirectional Data Flow, Process Death Survival, SavedStateHandle, and State Restoration Strategies
Most MVVM tutorials skip two key topics: state flow and process death. This guide covers Unidirectional Data Flow (state DOWN, events UP, single seale...
