React Native vs Flutter comparison - When to Use Which

The Big Idea

What if you could build one app that runs everywhere without doubling your work?

The Scenario

Imagine you want to build a mobile app that works on both iPhones and Android phones. You try to write separate apps for each platform using their own languages and tools.

You spend double the time, fix bugs twice, and keep two different codebases updated.

The Problem

Writing two separate apps means more work, more mistakes, and slower updates. It's like painting the same picture twice with different brushes.

It's hard to keep features and designs consistent, and fixing bugs in two places is frustrating.

The Solution

React Native and Flutter let you write one app that runs on both iOS and Android. They handle the tricky parts of making your app look and work right on each platform.

This saves time, reduces errors, and lets you focus on making your app great.

Before vs After

✗ Before

Write iOS app in Swift
Write Android app in Kotlin

✓ After

Write one app in React Native or Flutter

What It Enables

You can build beautiful, fast apps for both platforms with one codebase, reaching more users quickly and easily.

Real Life Example

A startup wants to launch their app fast on both iPhone and Android. Using React Native or Flutter, they build once and release everywhere, saving months of work.

Key Takeaways

Building separate apps is slow and costly.

React Native and Flutter let you write one app for both platforms.

This speeds development and keeps your app consistent.

Practice

1. Which language does React Native primarily use for building apps?

easy

A. Kotlin

B. Dart

C. JavaScript and JSX

D. Swift

Solution

1. Step 1: Identify React Native's programming language

   React Native uses JavaScript along with JSX syntax to build UI components.

2. Step 2: Compare with other options

   Dart is used by Flutter, Swift and Kotlin are native languages for iOS and Android respectively.

3. Final Answer:

   JavaScript and JSX -> Option C

4. Quick Check:

   React Native = JavaScript and JSX [OK]

Hint: React Native uses JavaScript, Flutter uses Dart [OK]

Common Mistakes:

• Confusing Flutter's Dart with React Native's JavaScript
• Thinking React Native uses native languages like Swift
• Assuming JSX is a separate language

2. Which of the following is the correct way to create a button in Flutter?

easy

A. <TouchableOpacity>Click</TouchableOpacity>

B. Button(title: 'Click')

C. <Button title='Click' />

D. ElevatedButton(onPressed: () {}, child: Text('Click'))

Solution

1. Step 1: Understand Flutter widget syntax

   Flutter uses Dart and widgets like ElevatedButton with named parameters.

2. Step 2: Identify correct button syntax

   ElevatedButton(onPressed: () {}, child: Text('Click')) uses ElevatedButton with onPressed callback and child Text widget, which is correct.

3. Final Answer:

   ElevatedButton(onPressed: () {}, child: Text('Click')) -> Option D

4. Quick Check:

   Flutter buttons use widgets with callbacks [OK]

Hint: Flutter buttons use widgets with onPressed callback [OK]

Common Mistakes:

• Using JSX or HTML-like syntax in Flutter
• Omitting onPressed callback in Flutter button
• Confusing React Native TouchableOpacity with Flutter widgets

3. What will be the output of this React Native code snippet?

import React from 'react';
import { Text, View } from 'react-native';

export default function App() {
  return (
    
      Hello from React Native!
    
  );
}

medium

A. A screen displaying the text: Hello from React Native!

B. A blank screen with no text

C. Syntax error due to missing import

D. App crashes on launch

Solution

1. Step 1: Analyze the React Native component

   The component returns a View containing a Text element with the string 'Hello from React Native!'.

2. Step 2: Understand rendering behavior

   React Native renders the View and Text properly, so the text will appear on screen.

3. Final Answer:

   A screen displaying the text: Hello from React Native! -> Option A

4. Quick Check:

   React Native renders JSX as UI [OK]

Hint: React Native JSX renders UI elements directly [OK]

Common Mistakes:

• Thinking View or Text won't render without styles
• Assuming missing styles cause crash
• Confusing React Native with web React

4. Identify the error in this Flutter code snippet:

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Text('Hello Flutter'),
      ),
    );
  }
}

medium

A. Missing @override annotation before build method

B. build method should return a Widget but returns void

C. Missing const keyword before MaterialApp

D. build method lacks override keyword and is missing @override

Solution

1. Step 1: Check Flutter build method requirements

   In Flutter, the build method should have the @override annotation to indicate it overrides a superclass method.

2. Step 2: Identify missing annotation

   The code lacks the @override annotation before the build method, which is a recommended practice to avoid errors.

3. Final Answer:

   Missing @override annotation before build method -> Option A

4. Quick Check:

   Flutter build methods need @override annotation [OK]

Hint: Always add @override before build in Flutter widgets [OK]

Common Mistakes:

• Ignoring missing @override annotation warnings
• Confusing const keyword necessity
• Thinking build returns void instead of Widget

5. You want to build a mobile app with highly customized UI components and smooth animations. Which framework is generally better suited for this need?

hard

A. React Native, because it uses native UI components by default

B. Flutter, because it offers more control over custom UI and animations

C. React Native, because it compiles to native ARM code

D. Flutter, because it uses JavaScript and JSX for UI

Solution

1. Step 1: Understand UI customization capabilities

   Flutter renders its own widgets and provides extensive control over UI and animations, allowing highly customized designs.

2. Step 2: Compare with React Native's approach

   React Native uses native UI components, which can limit deep customization and complex animations compared to Flutter.

3. Final Answer:

   Flutter, because it offers more control over custom UI and animations -> Option B

4. Quick Check:

   Flutter = better custom UI and animations [OK]

Hint: Flutter excels in custom UI and animations [OK]

Common Mistakes:

• Assuming React Native compiles to native ARM code
• Confusing Flutter's language as JavaScript
• Thinking native UI always means better customization