React Native Interview Questions and Answers for 2026

When we interview React Native developers at Creuto, the strongest candidates are not the ones who recite definitions. They explain why something works, give an example from an app they built and are honest about trade-offs. Practise these questions with that in mind.

Core concepts

1. What is React Native, and how is it different from React?

React Native uses React's component model to build native mobile apps. Instead of HTML elements it renders native views such as View and Text, so the interface is made of real platform components.

2. How is React Native different from a hybrid web view app?

Hybrid apps render a website inside a web view. React Native renders native components, which gives better performance and a more native feel.

3. What are props and state?

Props are inputs passed from a parent and are read-only in the child. State is data a component owns and changes over time, which triggers a re-render.

4. What do useEffect and useMemo do?

useEffect runs side effects such as data fetching after render, with dependencies controlling when it re-runs. useMemo caches an expensive calculation until its dependencies change.

The new architecture

5. What is the new React Native architecture?

It replaces the old asynchronous bridge with JSI, which lets JavaScript call native code directly. It includes Fabric, the new rendering system, and TurboModules, which load native modules lazily. The official architecture docs explain it in detail.

6. What is Hermes?

Hermes is a JavaScript engine optimised for React Native. It improves start-up time and memory use, and is the default engine in recent versions.

7. When would you write a native module?

When you need a platform feature or SDK that has no JavaScript library, or when a task is too heavy for JavaScript, such as advanced image processing.

State and navigation

8. How do you manage global state?

For small apps, React context is enough. Larger apps often use Redux Toolkit or Zustand for app state and a data library such as TanStack Query for server data and caching.

9. How does navigation work in React Native?

Most apps use React Navigation with stack, tab and drawer navigators. Know how to pass parameters, handle deep links and protect screens that need login.

Performance

10. How do you make a long list fast?

Use FlatList or FlashList instead of mapping inside a ScrollView, provide stable keys, keep row components light and memoised, and avoid creating new functions and objects on every render.

11. What causes unnecessary re-renders, and how do you fix them?

New object or function props, context values that change too often and state lifted higher than needed. React.memo, useCallback and splitting context help.

12. How do you find performance problems?

Measure first: use the React DevTools profiler, Flipper or platform tools, and test on low-end Android devices, not only on a fast phone.

Platform and release

13. How do you handle platform differences?

Use the Platform API or platform-specific files such as Component.ios.tsx and Component.android.tsx when behaviour or design must differ.

14. How do you store data securely on the device?

Use the iOS Keychain and Android Keystore through a secure storage library for tokens and secrets, never plain AsyncStorage.

15. How do you release an app to the stores?

Create signed builds, test them through TestFlight and Google Play testing tracks, prepare store listings and roll out in stages. Our guide on getting approved on the App Store and Google Play covers the review rules.

Testing

16. How do you test React Native apps?

Unit and component tests with Jest and React Native Testing Library, and end-to-end tests with a tool such as Detox or Maestro for critical flows like login and checkout.

Talk about your project

Expect questions such as "What was the hardest bug you fixed?" and "What would you change if you rebuilt it?" Prepare short stories with the problem, what you tried and the result. If you are deciding between frameworks, our comparison of React Native vs Flutter is a good refresher, and the React Native documentation is the reference to revise from.

Working at Creuto

At Creuto we build React Native apps for startups and businesses, and we hire remotely across India. See the React Native developer role and all open roles.