React Native vs Swift: Which is Better for Mobile App Development?
Tags: react, reactnative, swift, programming
Published: 2023-10-25 10:19:13

With over 3 million apps in the iOS App Store and over 2.7 million in the Google Play Store, it's clear that mobile apps are a huge part of our digital lives. When building a mobile app, one of the first decisions developers have to make is which platform and tools to use. The two most popular options today are React Native and Swift.

React Native allows you to build native iOS and Android apps using JavaScript and React. Swift is Apple's own programming language for building iOS, macOS, watchOS, and tvOS apps. Both have their pros and cons when it comes to [mobile app development](https://positiwise.com/services/mobile-application-development). In this comprehensive guide, we'll compare React Native and Swift across several factors to help you decide which is better for your next mobile app project.

React Native vs Swift - The Difference Table


|                | React Native | Swift |
|-|-|-|
| Language       | JavaScript | Swift |
| Compilation    | Just-in-time (JIT) | Ahead-of-time (AOT) |
| Architecture   | Cross-platform framework | Native iOS SDK |
| UI Rendering   | JavaScript thread | Main thread |
| Performance    | Slower | Faster |
| Access to APIs | Via bridges | Direct |
| Animations     | Not as smooth | Very smooth |  
| Startup Time   | Faster | Slower |
| Code Sharing   | Share code across iOS/Android | iOS only |
| Learning Curve | Easier for web devs | Steeper for beginners |
| Developer Support | Strong community | Strong official docs |
| App Size       | Larger | Smaller |

Basic Code Structure- React Native

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

export default function App() {
  return (
    <View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
      <Text>Hello, world!</Text>
    </View>
  );
}
```

- Uses JSX syntax to render UI
- Components, props, and state manage UI
- Runs on JavaScript thread using React Native bindings


Basic Code Structure- Swift

```swift
import UIKit

class ViewController: UIViewController {

  override func viewDidLoad() {
    super.viewDidLoad()
    
    let label = UILabel(frame: CGRect(x: 0, y: 0, width: 200, height: 50))
    label.text = "Hello, world!"
    label.textAlignment = .center
    
    view.addSubview(label)
  }

}
```

- Uses Swift language and Cocoa Touch frameworks
- UIKit views and controllers manage UI
- Runs on the main thread using native iOS APIs
The core difference is React Native uses JavaScript/React while Swift uses native iOS APIs. But they can both build mobile apps with native performance.


## Programming Language

React Native uses JavaScript for coding, whereas Swift has its own proprietary Swift programming language.

- JavaScript is immensely popular among web developers and has a huge community behind it. It's easy for front-end developers to get started with React Native since they can transfer their JavaScript knowledge. Swift has a smaller but rapidly growing community. It continues to gain popularity, especially among iOS developers.
- Swift takes inspiration from other languages like Python and Objective-C. The syntax is clean without too many complex concepts, making it relatively easy to learn, even for beginners.

Overall, JavaScript is better known, but Swift offers a more modern programming language tailored for Apple devices. Both languages have their merits, so this factor is a tie.

## Code Reusability

- A major advantage of React Native is code reusability. You can reuse around 90% of your code when building for both iOS and Android. Components and business logic only need to be written once in JavaScript. This significantly speeds up development and reduces costs compared to building native apps separately.
- With Swift, you have to build the iOS and Android apps natively in their own codebases. While SwiftUI and other frameworks reuse UI code, most of the business logic and native modules need to be rewritten for each platform.

React Native is the clear winner when it comes to code reusability. You get two apps for the price of one.

## Performance

- For performance, native Swift apps are faster and smoother. Swift has direct access to the full power of the device's hardware and OS. This allows apps to achieve 60 frames per second performance even on complex user interfaces.
- React Native provides near-native performance for most use cases. However, apps can suffer occasional stutters or lag, especially on lower-end devices. This is because React Native relies on a JavaScript bridge to communicate with the native code.

Therefore, Swift provides better performance, especially for games or complex visual apps. But React Native is fast enough for most business, e-commerce, and utility apps.

## Access to Native Features

- React Native allows access to many native device capabilities like camera, geolocation, etc, through its bridge modules. However, some very specific native features may not be available through React Native yet.
- Swift offers 100% direct native access to the entire iPhone and iPad functionality since it ultimately compiles native code. This includes the newest APIs that Apple releases each year.

As a result, Swift again wins when it comes to direct native feature access on Apple platforms. React Native plays catch up in terms of supporting the latest native APIs.

## User Experience

- Both Swift and React Native can be used to build beautifully designed apps with interactive user interfaces. Smooth animations, gestures, transitions, and 60fps scrolling can be achieved on both.
- React Native has a flexible UI framework. Complex UIs are constructed by nesting different components in a declarative way. SwiftUI provides a similar declarative UI building approach for Swift. These modern frameworks allow rapid UI development without manually laying out each view.

So, in terms of UX capabilities, both Swift and React Native score well. The experience will ultimately depend more on the designer’s skills rather than just the platform itself.

## Developer Productivity

- React Native offers faster development thanks to code reusability, a vast library of open-source components, and hot reloading. Hot reloading injects your changes instantly without recompiling the app.
- While Xcode also provides live previews, Swift's compile times can slow down development. SwiftUI's declarative syntax does improve productivity for UI code.

Overall, React Native streamlines mobile development, allowing you to do more with less code. A smaller React native team can develop at a faster clip than native iOS and Android teams.

## Going Cross-Platform

- A major consideration is portability across iOS, Android, and other platforms. With React Native, you can target both major mobile OSes without significant extra effort. This also makes it easier to launch on additional platforms like Windows or macOS in the future.
- Swift is designed specifically for Apple platforms like iOS, iPadOS, and macOS. While solutions like Xamarin allow cross-platform development with Swift/C#, they require more configuration and may compromise performance.

Therefore, React Native provides effortless cross-platform capabilities with a single codebase. Swift focuses on the excellence of Apple devices rather than portability.

## App Distribution and Updates

- To distribute React Native apps on the app stores, you submit them just like native apps. Users download them from the App Store or Play Store. Updates can be pushed seamlessly like native apps.
- Swift apps can be distributed through the App Store using Xcode. Seamless over-the-air updates are a major advantage of native apps. React Native apps also support OTA updates but may require extra configuration.

In terms of distribution, both Swift and React Native mobile apps work similarly to native apps. Pushing fixes and updates is easy on both platforms.

## Developer Ecosystem

- Both platforms have excellent support in terms of tutorials, guides, Stack Overflow questions, and an active community of developers. As JavaScript is more widely used globally, React Native has a bigger community than Swift right now.
- There is no shortage of third-party libraries and tools for both Swift and React Native. Apple develops and maintains Swift, so it provides excellent tooling in Xcode and SwiftUI. React Native has a thriving ecosystem created by the community.

Overall, both have excellent documentation and active communities around them. JavaScript's global dominance provides React Native with a small edge here.

## When to Choose React Native

Here are some of the best use cases for React Native:

- Building apps for both iOS and Android or expanding to additional platforms in the future
- Developing an MVP quickly and iteratively. React Native's hot reloading allows faster development cycles
- Apps that don't require extensive native functionality or super-high graphics performance
- Building complex user interfaces and transitions
- Maximizing code reuse across platforms. JavaScript talent is easy to find
- If web developers already on your team need to build mobile apps

## When to Choose Swift

Here are situations where Swift may be a better choice:

- Building apps exclusively for Apple devices like iPhone, iPad, Apple Watch, Apple TV, and Mac
- Apps that require complex and high-performance graphics like games and computer vision
- Leveraging the newest native features immediately as Apple releases them
- Building super high-performance apps where every bit of native power is needed
- Accessing new Apple SDKs and APIs not available in React Native yet
- If Swift developers are already part of your team
- Building iOS apps that may later be expanded to Mac with less effort

## Conclusion

React Native and Swift both allow building high-quality mobile apps, but ultimately cater to different use cases. React Native offers faster cross-platform development, while Swift provides unmatched access to native Apple ecosystem features.

If code reuse and portability are critical, such as for an early-stage startup, React Native is likely the best choice. It allows validating and launching your app on two platforms in the time it takes to build one native app.

On the other hand, Swift excels at delivering a truly native iOS experience. It's the best choice if you're only targeting iPhone and iPad users. Companies who prioritize the Apple ecosystem tend to standardize on Swift.

This guide gave you an overview of how React Native and Swift compare across a variety of factors. Consider your team's skills, app requirements, and business goals to decide the best platform for your next mobile app. With a thoughtful approach, you can maximize productivity and deliver an amazing experience.