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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Android Security for Banking & Enterprise Apps — Threat Model, Keystore, Cert Pinning, and the OEM Realities
The first time I worked on a banking app, I learned the threat model is fundamentally different. Consumer apps protect against bugs; banking apps prot...
System Design — Design Uber / Ride Sharing (Time-Scale Tiers and Spatial Real-Time Matching)
"Design Uber" is the first system design problem where real-time location is central. WhatsApp is about delivering bytes; Instagram is about choosing ...
Android Memory & Performance Interview Questions — 17 Investigation-Driven Prompts for Senior Roles
The performance round at a senior Android interview is rarely "define jank." It's "your app drops to 30fps when scrolling — walk me through your...
Android Architecture Interview Questions — 20 Scenario-Driven Prompts for Senior Roles
The architecture round is where most senior Android interviews are won or lost. The reason: architecture questions don't have textbook answers. "What ...
Compose Gestures Deep Dive — pointerInput, Multi-Touch, and Conflict Resolution
The high-level gesture APIs in Compose make 80% of cases trivial. Then someone hands you a photo editor needing pinch-to-zoom, rotation, draggable lay...
System Design — Design Instagram Feed (Push vs. Pull, the Decision That Shapes Everything)
What makes "design Instagram's feed" a great interview question is that it has one pivotal architectural decision and your answer reveals everything a...
DSA for Android Interviews 2026 — The Calibrated, Opinionated Roadmap
The DSA-for-Android-interviews advice on the internet is mostly wrong — not because the patterns are incorrect but because it's undifferentiated...
R8 / Proguard — The Mental Model, Keep Rules, and a Debugging Workflow That Actually Works
Every Android developer eventually ships a release that crashes on launch. Debug works perfectly. Then Crashlytics lights up with NoSuchMethodError &m...
Testing Retrofit & OkHttp with MockWebServer — From Setup to Network-Condition Simulation
The first time I had a production bug in a Retrofit API client — a header missing on one endpoint — I checked our tests and realized we we...
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...