What Is React.js and When To Choose It For App Development?

Kaja Grzybowska

What Is React.js and When To Choose It For App Development?

React.js, a JavaScript library invented almost a decade ago, has quickly become a third of the so-called Holy Trinity among Javascript frameworks (although technically it is closer to the library) next to Angular and Vue.js. However, "three" is already a crowd, and in the crowd, it is sometimes difficult to choose a solution that will meet our needs. To narrow the issue down, we will cover the basis ofReact.js and find out what makes it different from other popular solutions.

JavaScript - the Basis for React

JavaScript, which we used to blame for annoying pop-ups and crashing websites, unexpectedly settled down as the most popular pragmatic language worldwide, taking the whole front-end area and some back-end bridgeheads by storm. Today it is the most common coding language in use worldwide, and there is a solid reason for that skyrocketing popularity.

In the Stack Overflow Developer Survey, JavaScript has been voted the most commonly used programming language for the tenth year in a row.

When the general trend of shifting from server-side to client-side web applications started, the developers' eye turned to JavaScript, as it was the language that could "talk" with all available browsers and - let's be honest - was relatively easy to handle.

In fact, JavaScript is a genuine "multitasker." It can run on both the client and the server (with Node.js). Therefore, one Node developer can be hired to build both the server-side and client-end apps; it is scalable and has a vast community always eager to come up with an out-of-the-box solution to a given problem.

JavaScript has become a standard tool in web development responsible for how web pages and apps "behave." The typical tech stack behind most websites on today's internet includes HTML - the bones of the site, CSS - the skin, and JavaScript - the muscles that move the whole body. 

Thus, if JavaScript is everywhere, what's the fuss about choosing JS frameworks that, at some point, have been popping out of every corner? The answer is simple: developers have never stopped seeking new methods of improving efficiency. Even though JavaScript was considered easy to learn, it was obvious that working with it could be even more accessible. 

That is why the number of JS frameworks and libraries has grown significantly in modern times. Now, there is a whole ecosystem of comprehensive tools that enables developers to build almost everything they can imagine. It made working with pure JavaScript a bit old-fashioned and often counterproductive. Of course, JavaScript is still essential and needs to be understood, but with all these libraries and frameworks, JS developers' jobs can be done faster.

React Popularity

Currently, there are more than 1.2 million websites built with React.


  • 186k GitHub stars
  • 14.8k GitHub commits
  • 1.5k GitHub contributors
  • 376.4k questions on Stack Overflow
  • 2609k live websites

React’s communities are pretty fragmented so there are a few places where you can go to ask any question: DEV’s React community, Hashnode’s React community, Reactiflux chat on Discord, and Reddit.

What Is React?

React itself is technically more of a library than framework. However, the extensive ecosystem of React-related tools makes it can be placed somewhere between. 

Framework vs Library

  • Framework can be seen as a "skeleton" of an application, providing particular, ready-to-use elements as well as a general pattern of how to build the app within it.

  • Library is a set of functions that an application can call to perform a particular task.


On the one hand, it is not a full-blown framework per se, as it is insufficient to build a complete application, on the other - with the selected tools that are available - it is possible to cover every aspect of the given project.  

ReactJS vs React Native

  • React (ReactJS) — a library that enables developers to build websites that can work in the browser of any mobile device, regardless of the operating system.

  • React Native — a framework that allows building native apps for Android and iOS. 


Who Invented React?

React was created by Facebook and is still maintained by Meta and the vibrant community of companies and individual developers. But how did it start? Well, in 2011, when the growth of Facebook's Ad app got crazy, controlling and managing the code became overwhelming. It wasn't easy to keep up with the numerous updates, contributors, and stakeholders. To solve the problem, Jordan Walke created FaxJS, a ReactJS prototype that made this process significantly more efficient. 

The ReactJS career accelerated right after that when in 2012, Facebook bought Instagram. Back then, it was a modest photo app that had just 13 employees on board, but Facebook wanted to boost it by incorporating within it many of Facebook's new methodologies. It was, however, difficult with gated technologies, and the decision to decouple React from Facebook and make it open-source was taken. 

In late May 2013, Jordan Walke introduced React to the open-source world. The community started to play with it, and in 2014 when new features - such as the React Developer Tools and React Hot Loader came up, the interest exceeded expectations. 

In 2015, React was considered "stable" and gained the support of the companies such as Netflix, Airbnb, Microsoft, Dropbox, Asana, Yahoo, Codecademy, and Slack.

Why Is React One of the Frontend Leaders?

All three solutions - Angular, React and Vue - entrenched themselves in a leadership position in the frontend world, and every one of them has an engaged fan-base. Which one is the best? Well, the answer cannot be different that "it depends". 

React and Angular's support by such giants as - respectively - Facebook and Google that ensure their constant maintenance is obviously a solid argument in the ever-changing JS landscape. That is why many prominent companies go with one of these solutions instead Of open-source Vue.js. And yet, in the case of React, that is not the whole story. This solution is considered one of the most flexible on the market (which shouldn't come as a surprise since technically it is more of a library than a framework) but with the robust ecosystem of tools it can serve as a typical framework at the same time. 

Put it simply, it enables developers to build everything they want, without forcing them to use framework-specific methods. It makes React fast and easy to learn, especially compared to strongly opinionated Angular. 

React Primary Features


React is component-based. Components are the main building modules of React applications. These are reusable - class and functional - elements similar to JavaScript functions but working independently based on their own logic. 

JSX (JavaScript XML)

JSX is an extension of the JavaScript syntax used to "explain" React what the UI should look like. It is highly appreciated because of its visualization when working with the user interface. 

One-way data binding

It is a way of connecting UI elements with data that goes in one direction. This improves the performance, as when there is a change in the component, it will be seen in the view, and vice versa, with no interference with the whole code.

Virtual DOM

It is React’s local copy of HTML DOM that, by locally comparing elements, allows React libraries to render only actually changed components and save time by avoiding many unnecessary operations.


React, because of its impressive community, has a lot to offer. It’s lightweight enough to easily build multi-page apps but also good with single page ones. React is immensely useful for building scalable web apps (look at Facebook). React doesn't provide ready-made solutions for e.g. routing, so you need to use third-party libraries for that (Flux/Redux, and create-react-app scaffolding tool).

How Is It Different From Angular and Vue?

As we mentioned above, React is more of a library than a framework on contrary to Angular, a fully-fledged frontend framework, and also a Vue.js, which can be seen as a so-called progressive framework. 

It is true that they can be used interchangeably in developing frontend projects, yet it doesn't mean they are the same. In fact, their architecture differs a lot, but - instead of describing the code (it is always better to show it) - we will try to sketch the overall feeling related to React. 

And it is pretty interesting as - in the case of React - all of its pros can seem to be cons simultaneously. Let's take its flexibility, for example. On the experienced hand, it is a huge advantage - as the technology gives almost limitless possibilities for shaping products in alignment with business requirements. However, it can also be confusing and challenging – when there are many solutions to one problem, it is difficult to choose the best one.

However, JavaScript developers still love it. It allows them to use the JavaScript code instead of a framework-specific one, which makes it fast and easy to learn (especially compared to Angular which forces you to follow the strict rules). 

React provides mainly a library for rendering content to the DOM and controlling it, but it doesn't include built-in form validation support, a router for rendering different components, its own http client. So... compared to Angular it is quite modestly-equipped, but it doesn't have to be a problem with such a vibrant and supportive community. 

When to Choose React for App Development?

React's advantages are quite evident, yet it could still be hard to decide whether React should be chosen while developing an app. Indeed, React, when appropriately applied, can save time, effort, and cost of app development, but there are thousands of developers who would still opt for Angular or Vue instead of it. So is it possible to point out the objective criteria that suggest choosing React?

Let's try. Given React's flexibility, it seems a wise choice while working on a front-end UI that demands high user interaction. React lets developers focus on the interface's view model and keep the code relatively simple. It also implies a good performance, boosted by React's virtual DOM. Last but not least, React's popularity means that it is easy to dive into a broad talent pool and find the right people to get the job done. 

Choose React to: 

  • Build a complex solution/SPA
  • Have the possibility of expanding your app heavily in the future
  • Pick JavaScript over HTML
  • Have the backing of the most-used mobile development framework
  • Make use of immense database of third-party libraries


React is a great tool, appreciated by developers all over the world, and yet it is not a silver bullet or a remedy for all challenges that need to be tackled. It can help, cut development time and save cost, but it is still just a tool and it is good to remember that not the wand makes a wizard. 

Having said this, maybe the most appealing advantage of React is its popularity among developers, among whom many can actually make magic.

Kaja Grzybowska avatar
Kaja Grzybowska