Architecture
Prepare for the mobile architecture round on iOS, Android and Flutter: module boundaries, dependency direction, state ownership and defending your pattern.
Question bank · no interactive practice yet
React Native interview prep
Senior React Native interviews test the boundary: what happens between JavaScript and native, where performance goes, and when you would write a native module instead of another dependency.
What the React Native loop scores
| Round | What the interviewer writes down |
|---|---|
| JavaScript and React | Rendering, memoisation and effects, explained from a real screen. |
| The native boundary | The new architecture (JSI, Fabric, TurboModules) and what it changed in practice. |
| Performance | Lists, images, animations and how you measured the problem. |
| State and data | Where the source of truth lives and how offline behaves. |
Loops differ by company. This is the common shape of senior loops, not a promise about any one employer.
The second question
Follow-ups that decide the round
“The list drops frames on Android only. Where do you start?”
Tests whether you can separate a JavaScript problem from a native one.
“Would you write this as a native module? Why?”
Tests judgement about the boundary, not loyalty to a framework.
How to prepare, by the time you have
A week or less
Rendering and memoisation, the new architecture, and one performance problem you measured.
Two to four weeks
Work through the question bank by area, answering out loud first; add one design scenario with offline behaviour.
Senior loop
Be ready to say when you would write a native module instead of adding a dependency, and why.
Prepare by round
The same rounds appear on every platform. Each page says what the round scores and which guides go deep.
Mobile system design
Prepare for the mobile system design round: offline behaviour, sync, caching, lifecycle and release, and what the interviewer scores at Senior and Staff.
Coding and live coding
Prepare for mobile coding, live coding and pair programming rounds: the tasks that recur, how they are graded, and what to say while you type.
Senior and Staff
What changes in a Senior or Staff mobile interview loop: the follow-up depth, the scope of the design round, and the evidence each level is expected to show.
React Native interview guides
React Native · 14 min
React Native interview questions and answers
Twelve React Native interview questions on rendering, lists, effects, the New Architecture, Hermes and storage, with what is scored, the trap and the follow-up.
React Native · 13 min
Senior React Native interview questions and follow-ups
Ten senior React Native interview questions on migration, startup, retries, old app versions, feature flags and native rewrites, with the follow-up to each.
Across platforms
Mobile system design · 17 min
Mobile system design interview: how the round is scored
How a mobile system design round runs, the seven things a senior answer covers, a worked offline sync example, and how Senior and Staff are scored.
Senior and Staff loops · 11 min
Mobile architecture interview questions, any platform
Architecture interview questions that do not depend on the platform: modules, shared code, server-driven UI, flags, old app versions and who owns what.
Live coding · 14 min
Mobile live coding interview: what to say while you type
How a mobile live coding round is scored, a 45-minute plan, what to say at each stage, a worked Swift example, and how to recover when you stall.
Practice
There is no interactive React Native practice yet, and this site will not pretend there is. The question bank above is the honest starting point: answer each question out loud before you read the answer. How to practise without a tool.