Introduction: What is Cross-Platform Mobile App Development.

Multiplatform mobile development is an approach that allows you to build a single mobile application that runs smoothly on several operating systems. In simple words a Cross-Platform Development uses one source code on both platforms, thus developers can create and deploy files/assets/commits that work on both Android and iOS without having to recode them for each individual platform when using native languges like Objective-C, Swift, Java or Kotlin.

A Brief Overview of React Native & Flutter and Their Features

TLDR: They are both very similar.

What is React Native?

React Native is a mobile development framework created by Facebook and released in 2015. React Native also lets you build cross-platform applications for a number of platforms and operating systems.

React Native

React Native provides access to several third-party UI libraries with ready-to-use components, helping mobile engineers save time during the development process. Like Flutter, it allows you to see all your changes immediately, thanks to the Fast Refresh feature.

You should consider using React Native for your app in the following cases:

• Your application is relatively simple and is expected to be lightweight.
• The development team is fluent in JavaScript or React.
• Really good for quick MVP validation.

Applications built with React Native include Facebook, Instagram, Skype, and Uber Eats.

React Native has a vast community of developers who have contributed to its ecosystem and libraries, and with the increasing competition, React Native is also improving its features and performance.

What is Flutter?

Flutter is a user interface (UI) software development kit released by Google in 2018. Flutter lets you build cross-platform applications for a number of platforms and operating systems.

Apps built with Flutter need to share all of their UX and UI layers, which is why they may not always feel 100% native. One of the best things about this framework is its Hot Reload feature, which allows developers to make changes and view them instantly.

This framework may be the best option in the following situations:

• You want to share UI components between your apps but you want your applications to look close to native.
• The app is expected to put a heavy load on CPU/GPU.
• You need to develop an MVP application.

Among the most popular apps built with Flutter are Google Ads, Xianyu by Alibaba, eBay Motors.

Flutter is a relatively new entrant but has shown promising results. It uses the Dart programming language, which is a more modern and intuitive language than JavaScript.

What’s the Difference Between React Native and Flutter?

The main difference is that React Native is based on the JavaScriptCore runtime and Babel transformers and is similar to React JS which is used to build the user interface of web applications (that is, apps that run on a web browser). Hence popularity and ease of use by all the JS developers.

Flutter is different because it only has a thin layer of C/C++ code. Flutter implements most of its system (compositing, gestures, animation, framework, widgets, etc) in Dart programming language.

UI Components

Flutter renders all components on its own canvas.  React Native transforms JavaScript components into native ones. Because of that, component updates don’t have any impact on Flutter apps but do on React Native apps. If there is a need for components to stay exactly the same regardles of newest IOS or Android updates, Flutter’s approach will be better.

If we need an app to update to latest native component designs, then React Native updates happens automatically and are free. To include the latest native components in Flutter, there will be a need for a developer to update the app manually, which could add couple hours to the overall bill.  If we don't want components in a React Native app to follow the new iOS design there is an simple option to turn the automatic component update off.

Comparing React Native vs. Flutter in Terms of Performance

Flutter is designed to render its UI at 60 frames per second (fps), or 120 fps on devices capable of 120Hz updates. Each render is called a frame. This means that, approximately every 16ms, the UI updates to reflect animations or other changes to the UI.

Flutter https://docs.flutter.dev/perf

When running a React Native app on a device that has a refresh rate other than 60, react native apps still run at 60 fps. This means that if you have a device which runs at 120 fps, every react native app will feel sluggish, slow and underperforming. It means User Experience can be a bit donwgraded on React Native apps in comparison to the Flutter that will grow naturally while each year more devices having 120Hz and 120fps screens.

React Native https://reactnative.dev/docs/performance

Who Will Win the Popularity Battle of Cross-Platform Mobile App Development

React Native has been a popular choice for many years due to its ease of use, popularity of JavaScript frameworks and the ability to build apps for both iOS and Android with a single codebase. However, Flutter has been gaining momentum in recent years due to its speed and performance.

In 2023, we can see React Native and Flutter finally level up in popularity even with the slight advantage to Flutter. React Native remains a stable and reliable choice for building cross-platform apps, while Flutter continue to gain popularity due to its unique features and capabilities.

Popularity

Looking at the current trend, Flutter seems to be gaining popularity among developers due to its features like high performance, hot-reload feature, and customizable widgets. On the other hand, React Native has been in the market for a long time and has a stable user base but is slowly fading.

Ultimately, the choice between React Native and Flutter will depend on the specific needs of each project. Developers will need to consider factors such as app complexity, user experience, and development time when choosing the best framework for their project. StackOverflow in its survey shows that more developers are happy with Flutter than React Native and more are willing to learn Flutter.

Conclusion

Both React Native and Flutter have their pros and cons, and the choice of which one to use will depend on the specific needs of each project. However, it's safe to say that both will continue to be strong contenders in the mobile development world, and we can expect exciting developments from them in the future. In conclusion, we can guess that Flutter will be the ultimate winner of the cross-platform framework, but React Native will not fade out for many years to come.

As a Founder, you probably want to know which one to choose. First, we need to consider if you need to quickly validate your MVP and have a bit cheaper framework with more accessible developers. Then the good choice is React Native. If you plan to build a large app where speed and performance are necessary from day one after the release (a large number of users, or heavy functions), then the better choice would be Flutter. But as mentioned in the article, both are very similar, and React Native is also a good choice and could be better in terms of talent access and the specific needs of your mobile application. It's always best to ask a technical staff/advisor which framework matches your requirements best.