Flutter vs React Native: Key Differences and When to Use Each

Flutter uses Dart and compiles to native code with its own rendering engine, offering consistent UI across platforms. React Native uses JavaScript and native components, relying on a bridge for communication, which can affect performance but allows easier integration with native code.

Quick Comparison

Here is a quick side-by-side comparison of Flutter and React Native on key factors.

Factor	Flutter	React Native
Programming Language	Dart	JavaScript
UI Rendering	Own rendering engine (Skia)	Native components
Performance	Near-native, compiled ahead-of-time	Good, uses bridge for native calls
Development Experience	Hot reload, strong typing	Hot reload, dynamic typing
Platform Support	iOS, Android, Web, Desktop	iOS, Android, Web (via extra libs)
Community & Libraries	Growing, official widgets	Large, many third-party libs

Key Differences

Flutter uses the Dart language and compiles its code ahead-of-time into native ARM code. It draws every pixel on the screen using its own rendering engine called Skia, which means the UI looks consistent across all platforms but can increase app size.

React Native uses JavaScript and relies on a bridge to communicate with native platform components. It uses native UI elements, so the app looks more like a native app but can have performance overhead due to the bridge.

Flutter offers a rich set of customizable widgets and a single codebase for mobile, web, and desktop. React Native has a larger ecosystem with many third-party libraries and easier integration with existing native apps, but UI consistency depends on native platform differences.

Code Comparison

Here is a simple example showing how to create a button that shows a message when pressed in Flutter.

dart

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('Flutter Button')),
        body: Center(
          child: ElevatedButton(
            onPressed: () {
              print('Button pressed');
            },
            child: Text('Press me'),
          ),
        ),
      ),
    );
  }
}

Output

A screen with an app bar titled 'Flutter Button' and a centered button labeled 'Press me'. Pressing the button prints 'Button pressed' to the console.

React Native Equivalent

Here is the equivalent React Native code for the same button functionality.

javascript

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

export default function App() {
  return (
    <View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
      <Button
        title="Press me"
        onPress={() => Alert.alert('Button pressed')}
      />
    </View>
  );
}

Output

A screen with a centered button labeled 'Press me'. Pressing the button shows an alert popup with 'Button pressed'.

When to Use Which

Choose Flutter when you want consistent UI across platforms, need high performance, and prefer a single codebase for mobile, web, and desktop. It is great for apps requiring custom designs and smooth animations.

Choose React Native if you prefer JavaScript, want faster integration with existing native apps, or rely on a large ecosystem of third-party libraries. It suits projects where native look and feel is important and you want to leverage web development skills.

Key Takeaways

Flutter uses Dart and its own rendering engine for consistent, high-performance UI.

React Native uses JavaScript and native components, relying on a bridge that can affect performance.

Flutter supports mobile, web, and desktop from one codebase; React Native focuses mainly on mobile with web via extra tools.

Flutter offers rich customizable widgets; React Native has a larger ecosystem and easier native integration.

Choose Flutter for custom UI and cross-platform consistency; choose React Native for native feel and JavaScript ecosystem.