React Native mock test: free online practice

What does the React Native mock test cover?

The test covers 13 topics across three levels. Each attempt picks 15 to 30 questions at random, by the level you choose, so every attempt is different.

• JavaScript Essentials
• State and Hooks
• Build, Release and Expo
• Lists and Performance
• Native Modules and New Architecture
• Networking and Storage
• Animations and Gestures
• Navigation
• Styling and Flexbox
• Debugging and Tooling
• Core Components
• Permissions and Device APIs
• Platform-specific Code

Sample React Native mock test questions

One question from each level, the way they appear in the test. A new set comes on the 1st of every month. Try it, then open the answer.

1. FresherStyling and Flexbox

   How tall is the second child View?

   <View style={{ height: 300 }}>
       <View style={{ flex: 1 }} />
       <View style={{ flex: 2 }} />
   </View>

   • 150
   • 300
   • 200
   • 100
   Show the answer

   Answer: 200. With the default column direction, flex shares the 300 of height in the ratio 1:2, so the first child gets 100 and the second gets 200. flex always works along the main axis, which here is vertical.

2. Intermediate (1-5 years)Core Components

   Which prop cuts a long product name to two lines that end with ...?

   • numberOfLines={2}
   • ellipsize={2}
   • maxLines={2}
   • lines={2}
   Show the answer

   Answer: numberOfLines={2}. numberOfLines limits the rendered lines, and ellipsizeMode defaults to 'tail', so the cut text ends with an ellipsis. A fixed height would clip the text in the middle of a line, with no ellipsis.

3. Experienced (5+ years)Animations and Gestures

   In Reanimated 3, how long does withSpring(1) take by default?

   • No fixed time: it settles by stiffness, damping and mass
   • Exactly 300 ms, the same default as withTiming
   • As long as the JS thread allows it to keep running
   • Exactly 1 second, unless you pass a different duration option
   Show the answer

   Answer: No fixed time: it settles by stiffness, damping and mass. A spring runs until it comes to rest, so its length depends on its physics config and starting velocity, which feels natural after a fling. withTiming is the choice when you need an exact duration.

Take the full React Native mock test: 15 to 30 questions and 15 to 30 minutes, by level.

How is the React Native mock test scored?

A question counts as right only when you pick exactly the right option, or all the right options where it says so; a question left blank counts as wrong. Your score is the share of the test's questions you got right (15 to 30, by level). The result also scores every topic, so you know what to revise before the interview.

• 75% or more in a topica strength
• 50% to 74%worth a revision
• Under 50%a topic to work on