Marketing
May 26, 2025
React Native lets you build truly native iOS and Android apps using JavaScript and React. Accelerate your mobile app delivery by talking to a MetaCTO expert today.
Chris Fitkin
Founding Partner
React Native has emerged as a transformative force in the mobile app development landscape. For businesses and developers looking to create high-quality, native mobile applications for multiple platforms without managing separate codebases, React Native offers a compelling solution. This framework, born out of Facebook’s internal needs, has democratized native app development by leveraging the power and familiarity of JavaScript and the React library.
In this comprehensive guide, we will delve deep into what React Native is, explore the intricacies of its architecture, understand how it’s used in modern app development, showcase its widespread adoption by leading global companies, and discuss potential alternatives. Crucially, we will also address the challenges that can arise when integrating React Native into mobile app projects and how partnering with an experienced development agency like us, MetaCTO, can ensure a smooth and successful implementation. With our 20 years of app development experience and a track record of over 120 successful projects, we are adept at harnessing the full potential of React Native.
At its core, React Native is a best-in-class JavaScript library designed for building user interfaces, specifically for mobile platforms. It ingeniously brings the best parts of developing with React to native development. If you’re familiar with React for web development, you’ll find the programming paradigm and component-based architecture quite familiar. However, instead of rendering components to the browser’s DOM, React Native takes a different, more powerful approach.
The magic of React Native lies in its ability to allow developers to write applications in JavaScript, which are then rendered with native code. This means that applications built with React Native are not mere web apps packaged in a native shell; rather, React Native lets you create truly native apps. The distinction is critical: React primitives render to native platform UI, meaning the buttons, text fields, and views your users interact with are the actual native components of iOS and Android. This ensures that React Native apps use the same native platform APIs other apps do, delivering the performance, look, and feel that users expect from native applications.
To facilitate this, React Native provides a core set of platform-agnostic native components like View, Text, and Image. These components are JavaScript abstractions that map directly to the platform’s native UI building blocks. For example, a <View> component in React Native might render as an UIView on iOS and an android.view.View on Android. This approach effectively brings the React programming paradigm to platforms like Android and iOS, enabling developers to build cross-platform applications with a single codebase while still achieving native performance and user experience.
Understanding the architecture of React Native is key to appreciating its capabilities and limitations. It’s a sophisticated system designed to bridge the gap between JavaScript and the native environments of mobile operating systems.
The fundamental idea behind React Native is to combine JavaScript code and Native code. Native code refers to languages like Java/Kotlin for Android and Objective-C/Swift for iOS. While the native code will be executed directly on the device, JavaScript, being an interpreted language, needs a virtual machine (VM) to be run on.
Fortunately, iOS devices have a built-in JavaScript engine called JavaScriptCore, which is written in C++. This engine will compile and execute JavaScript code on iOS. Android devices, however, do not have a built-in JS engine suitable for this purpose. Therefore, JavaScriptCore will be brought along with the React Native framework on Android devices, ensuring a consistent JavaScript execution environment across platforms.
A significant challenge arises because Java/Obj-C and JavaScript are different programming languages and cannot speak directly to each other. React Native historically solved this by enabling them to speak indirectly by using JSON (JavaScript Object Notation) as a common data format. This communication between Java/Obj-C and JavaScript is handled by a set of programs called the Bridge.
The Bridge acts as an intermediary, transferring serialized messages between the JavaScript realm (where your application logic resides) and the Native realm (where UI rendering and native API access occur). This process involves:
This Bridge is asynchronous, meaning that sending a message doesn’t block the sender; the response, if any, will come back later. This asynchronicity is crucial for maintaining a responsive UI, but it also means that communication has an inherent latency due to the serialization, transmission, and deserialization steps. Messages transferred by the Bridge will then be deserialized and processed by the receiving realm.
When you build a React Native application, several compilation and bundling steps occur:
At runtime, a React Native application isn’t just a single process. Several key threads work in concert:
When a user runs a React Native application, the device will start these three main threads, and additional background threads if needed for tasks like network requests or heavy computations.
The interaction flow mediated by the Bridge typically looks like this:
This constant back-and-forth communication is what makes the application interactive.
Recognizing the performance bottleneck and complexities associated with the Bridge, the React Native team has been working on a new architecture. Starting from version 0.68, it’s possible to use the new React Native architecture, which significantly changes how JavaScript and native code interact.
The cornerstone of this new architecture is the JavaScript Interface (JSI). JSI is a unified, lightweight, general-purpose layer that drops the Bridge mechanism. A key advantage of JSI is that it could be utilized in any JavaScript engine, not just JavaScriptCore.
With JSI, React Native can make direct connections to native APIs. Instead of asynchronous, serialized messages, JSI allows JavaScript to hold direct references to C++ objects and invoke their methods. Here’s how it works:
This direct invocation means that communication can be synchronous on the same thread if needed, eliminating the overhead of serialization/deserialization and asynchronous message passing for certain operations. It can also be asynchronous by creating a new thread if the operation is long-running. This evolution promises significant performance improvements, more direct control, and a more streamlined development experience for complex native integrations.
Developing with React Native combines the flexibility of JavaScript with the power of native platform capabilities. Here’s how developers typically approach building apps with it:
The primary goal when using React Native is to create native apps for Android, iOS, and more using React Native. As we’ve established, it brings the best parts of developing with React to native development. This means developers familiar with React for the web can leverage their existing skills to build mobile experiences.
Developers primarily use React Native’s core set of platform-agnostic native components like View, Text, and Image. These components are the basic building blocks for UIs. For instance, a code example would show how these components can be written in JavaScript, rendering UI using elements like View and Text.
import React from 'react';
import { StyleSheet, Text, View } from 'react-native';
const App = () => {
return (
<View style={styles.container}>
<Text style={styles.title}>Hello, React Native!</Text>
<Text style={styles.subtitle}>This is a native app.</Text>
</View>
);
};
const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent: 'center',
alignItems: 'center',
backgroundColor: '#F5FCFF',
},
title: {
fontSize: 20,
textAlign: 'center',
margin: 10,
},
subtitle: {
textAlign: 'center',
color: '#333333',
marginBottom: 5,
},
});
export default App;In this simple example, <View> acts as a container (similar to <div> in HTML), and <Text> is used for displaying text. The styling is done using JavaScript objects, often leveraging a flexbox-like layout system provided by Yoga.
To build a new app with React Native, the article recommends a framework like Expo. Expo is a set of tools and services built around React Native that simplifies many aspects of development, such as project setup, building, and deployment.
React Native also offers robust features for building complex applications:
The true testament to React Native’s capabilities is its adoption by some of the world’s largest technology companies and a multitude of startups. It’s not just for simple apps; React Native powers complex, high-traffic applications across various industries.
As the creator of React Native, Meta extensively uses it across its suite of products:
Microsoft is another major proponent, leveraging React Native to deliver excellent customer experiences in some of its most well-known apps and notably to target desktop platforms as well:
Amazon has been an early adopter, using React Native to rapidly deliver new customer-facing features in some of its most popular mobile applications as early as 2016. They also use it to support customer-favorite devices such as the Kindle E-readers:
The e-commerce giant has made a significant commitment: all new mobile apps at Shopify are React Native. They are also actively migrating its flagship merchant admin app Shopify Mobile to React Native.
Wix, a leading website building platform, uses React Native for its entire suite of applications, demonstrating its versatility:
These examples highlight React Native’s ability to scale, perform, and deliver rich user experiences across diverse application types, from social media and e-commerce to productivity and enterprise tools.
While React Native offers a unique blend of JavaScript development with native performance, it’s helpful to understand its position relative to other app development approaches:
Native Development: The most direct alternative is to build separate apps for each platform using their native languages and SDKs:
Other Cross-Platform Frameworks: Several other frameworks aim to solve the cross-platform challenge. One such example from the provided list of technologies is NativeScript. NativeScript allows developers to build native mobile applications using JavaScript, TypeScript, or Angular. Like React Native, it provides direct access to native APIs. Other frameworks exist in the market, each with its own philosophy, strengths, and trade-offs regarding performance, native feel, and development experience.
React Native’s distinction often lies in its ""learn once, write anywhere"" philosophy, leveraging the massive React ecosystem, and its approach of ""JavaScript written, rendered with native code,"" which aims for a no-compromise native experience. The new architecture with JSI further solidifies its position as a high-performance cross-platform solution.
Despite its numerous advantages, integrating React Native, especially into existing projects or for highly complex applications, can present challenges. This is where deep expertise and strategic planning become crucial.
At MetaCTO, we understand these challenges intimately. We’ve successfully navigated the complexities of React Native development and integration for a diverse range of clients. Our approach is built on deep technical expertise and strategic insight:
Integrating React Native isn’t just about writing JavaScript; it’s about understanding how to make two distinct worlds—JavaScript and Native—work together harmoniously. With MetaCTO, you’re not just hiring developers; you’re partnering with a team that has a proven track record, exemplified by our 5-star rating on Clutch and $40M+ in fundraising support for our clients. We can help you overcome the hurdles and unlock the true potential of React Native for your mobile app.
Throughout this article, we’ve journeyed through the landscape of React Native. We started by defining what React Native is: a powerful JavaScript library that allows developers to build truly native applications for iOS and Android (and beyond) using React’s paradigm. We then delved into how React Native works, exploring its architecture from the traditional Bridge mechanism that facilitates communication between JavaScript and native code via JSON messages, to the runtime environment involving the Main, JavaScript, and Shadow threads, and the crucial role of the Yoga layout engine. We also touched upon the exciting advancements with the new architecture featuring the JavaScript Interface (JSI), promising more direct and synchronous communication.
We explored how to use React Native, from leveraging core components and tools like Expo for rapid development to its flexibility in integrating custom native code. The impressive use cases for React Native showcased its adoption by tech giants like Meta, Microsoft, Amazon, Shopify, and Wix, proving its mettle in powering complex, high-scale applications across diverse platforms.
Finally, we addressed the important considerations of why integrating React Native can sometimes be challenging, highlighting potential issues with native dependencies, API integrations, and performance for highly intensive tasks. This is where expertise matters.
If you’re looking to leverage the speed, efficiency, and cross-platform capabilities of React Native for your mobile application, or if you’re facing challenges integrating it into your existing product, MetaCTO is here to help. Our team of experts specializes in React Native development and integration, ensuring your project benefits from the best of both web and native worlds.
Don’t let the complexities of cross-platform development hold you back. Talk with a React Native expert at MetaCTO today to discuss how we can seamlessly integrate React Native into your product and help you achieve your mobile app goals.
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