Even though React.js and React Native have similar titles, they stand for different concepts. Actually, it’s quite inaccurate to make a direct comparison between them, as they have different purposes. Both were created by Facebook to improve the performance of the application and make user experience with the social network more pleasant. Yet, React Native is a framework for building apps, whereas React.js — here, we also call it React — is a library for creating responsive user interfaces (UIs). Anyway, we’ll discuss the characteristics of both and even draw connections between them rather than compare.

What is React.js?

React is a JavaScript-based library with an extensive ecosystem dedicated to building dynamic user interfaces. Despite being a library, React is often compared to frameworks such as Vue, Ember, Preact, and Angular for building declarative and component-based UIs. It is also praised for its effective and powerful mental model. Let’s dig a bit deeper in what it means.

Components are bricks with which you build an interface. Most often they represent elements of the UI: navigation panels, titles, calendars, etc. Or they stand for certain functions, e.g. data formatting. If you need a unique component, you only have to build one and then reuse it.

The components are rendered based on data updates through virtual DOM, which makes interaction with an interface seamless for the user. From the user’s point of view, the screen appears the same, with minor changes in elements, such as the fluctuating number of likes. To put it simply, the user gets interactive, or dynamic, UIs, while React updates and renders data when it changes.

It means that when a user takes an action on the page, it does not require reloading or opening the next page. The declarative nature of React.js helps users to stay on the same page on their Facebook, Twitter, or Instagram.

It relies on complex areas of computer science and software engineering. React uses functional and object-oriented programming concepts. What truly drives React’s power are its building elements, called components. They are automatically synchronized with the app’s view by the React rendering system, making it convenient to build any UIs without any worries about how the data is managed.

What is React Native?

React Native framework should be seen as a part of the React.js ecosystem built by Facebook. It allows the creation of easily updated React apps for Android, iOS, Linux, macOS, and Windows. For now, it is a great framework for cross-platform mobile development, however, Meta is working on expanding it to web and VR engineering.

Before React Native was introduced, cross-platform development was still possible, but it didn’t allow programmers to build apps with native code. To create an app for Android and iOS platforms, the knowledge of two different languages was necessary: Kotlin or Java for the first one and Swift or Objective-C for the latter.

Some companies use React Native for building additional elements for their existing native apps without rewriting the whole app. Pinterest used the framework for implementing a Topic Picker feature. And vice versa, with React Native, you can write JavaScript apps using native code and compile it for different platforms.

The framework supports hot reloading, which suits for implementing updates and bug fixing without updating the app manually. The overall state of the app stays the same, and only modified code changes. The feature is profitable both for the companies and developers in terms of development speed and management simplicity.

Meta has already extended its use for desktop applications by introducing the Many Platform Vision back in 2021. By that time, Meta had already improved the video calling experience for a Microsoft desktop app. Nowadays, all core Microsoft apps built are powered by React Native. So, yes, React Native is truly cross-platform and supports development for the desktop.

Find what global companies use React Native framework in the article Best Apps Built with React Native

Connection between React and React Native

We’ve looked through the characteristics of the two technologies separately. Now, let’s talk about their connection, as differences must be obvious now. Actually, their bond is inseparable, as React Native runs on React.js. Both share the same syntax called JSX, which is an extension of JavaScript. Basically, to build a product with React Native, it is essential for the developer to have profound knowledge of the React library. What are other binding ties?

React Native doesn’t work without React. You can use React without React Native for building UIs for the web. However, you cannot use React Native without knowing React. With the use of React, you build the UI and make custom components for it — we’ve spoken about convenient reusable React components earlier. And, with React, you set up props and states to create customized and intuitive interaction for the user.

They have the same one-directional information flow. Because React Native was inspired by React, they share a similar way of handling component hierarchy. A one-directional data flow provides better control of the state and prevents errors.

It’s easy to switch from frontend to mobile development knowing React.js. The only thing to learn will be native components that make apps look as if they were built with Swift or Kotlin. These are tools that invoke appropriate views for native platforms, iOS or Android.

Most JavaScript libraries compatible with React work with React Native as well. Libraries for non-UI utilities such as data fetching and state management (Redux) are easily shared by both technologies. It means that developers can use the same libraries and codebase for both their web and mobile applications, saving them time and effort in the development process.

React Native apps can run in web browsers as well as React applications. While React Native is primarily used for developing mobile apps, it has growing and constantly improving web support. It aims to match the level of web apps built with React.

Use cases

There are well-known examples of apps most of us use on a daily basis; these are by such companies as Meta, Microsoft, or Pinterest. Nevertheless, the React ecosystem doesn’t only work for complex solutions. However React.js and React Native can be both cost and time-effective solutions for any kind of app. These are technologies we extensively use to develop projects for our clients. Let us introduce a few examples.

Social app for the community of bettors

The OddsCrowd application originally existed in a web version only, and the founders wanted to introduce a mobile app before the Super Bowl event. The mobile version for Android and iOS platforms was built with the use of React Native.

The reason to choose the framework was its time-effectiveness provided by the possibility of cross-platform development. To make a robust app, we used React Native-based ready solutions. We utilized Expo for its tools, application development, and testing capabilities, as well as Expo-Notifications for push notifications.

The team managed to develop an app within ten weeks by the start of the Super Bowl. The implementation of a cross-platform mobile app involved more bettors in the app, so shortly after the release, the monthly number of users increased by ten times.

Web application for booking unusual stays in the UK

UKR Club app by UK Retreats represents a map of unique apartments for rent across GB. Our goal was to make an MVP in a short period of time, while at the same time making it in a way that allows the app to scale in the future as it grows in number of users.

Thus, we made a front part of a web app with React. The library provides flexibility in terms of updates, and the React Router used with React will help to add new features if needed. The backend was developed with Laravel Nova framework.

We completed the project within three months. And the partnership with UK Retreats resulted in over 850 sign-ups after the first month.

App supporting an eco-friendly renting service in Finland

The Lainappi app aims to give a second life to unwanted items, to give and take things for rent via special boxes. At first, we wanted to start with building an Android app and then proceed to iOS development, but then together with the Lainappi team decided to make a hybrid app that would cover more of the audience right from the start.

React Native helped to accelerate the development process. We leveraged react-native-maps and expo-location libraries to quickly integrate map and user location features for both iOS and Android. To achieve a Loosely Coupled Architecture with reusable and adaptable components, we utilized a combination of React and Redux.

The decision to develop a hybrid app turned out to be the right one, as the app showed an equal number of first downloads on both platforms: 3,088 on iOS and 3,096 on Android.

Wrapping up

Perhaps, when getting acquainted with React and React Native, it is better not to focus on their differences, but to think about how the combination of these tools can be useful in creating cool applications.

The speed of cross-platform development and the fact that since the 2010s the framework and library have remained one of the most popular, allows us to have no doubts about the effectiveness of these tools. The experience of developing applications for our clients has also shown that the React ecosystem is the most preferable way to launch a product on multiple platforms. The result of this choice is reduced time to market and better lead generation.