7 Useful JavaScript Libraries To Build a Real-Time Web App

Originally posted on dev.

When it comes to creating a real-time application, you need to consider a lot of things. It needs to be fast and perform well even with heavy usage. Moreover, security is also an important factor that has to be taken into account. All these factors make it challenging for developers to build such a platform. But fortunately, we have various JavaScript libraries that can simplify the process and help you create a real-time web app easily. In this post, we will look at some of the useful JavaScript libraries that can make your life easier when developing such an application.

1. Socket.io

Socket.io is one of the best cross-browser JavaScript library that provides event-driven communication capabilities for use in real-time applications. It allows bi-directional communication between client and server. Bi-directional communications are enabled when a client has Socket.IO in the browser, and a server has also integrated the Socket.IO package.

2. WS

With over 19k stars on GitHub and about 60 million weekly downloads on npm, ws is one of the most popular open-source libraries for real-time web application development

ws is a fast, easy-to-use, well-documented, and thoroughly-tested WebSocket client and server implementation that supports almost all browsers. As a result, ws is a favorite, go-to library for many developers, meaning its community is active and robust.

3. SockJs

SockJS is a JavaScript library that provides communication between the client and the server in a way similar to the native WebSockets API. SockJS functions with a server counterpart in the form of sockjs-node and SockJS-client, a JavaScript client library.

With over 8k stars on GitHub and almost 11 million weekly downloads on npm at the time of writing, SockJS is arguably one of the best JavaScrit libraries to build real-time web applications. SockJS follows the rules of the HTML5 WebSocket API and provides objects similar to WebSocket.

4. Pusher

Pusher is a hosted service that makes it super-easy to add real-time data and functionality to web and mobile applications. It sits as a real-time layer between your servers and your clients. Pusher maintains persistent connections to the clients — over WebSocket if possible and falling back to HTTP-based connectivity — so that as soon as your servers have new data that they want to push to the clients they can do, instantly via Pusher.

Pusher offers libraries to integrate into all the main runtimes and frameworks. PHP, Ruby, Python, Java, .NET, Go and Node on the server and JavaScript, Objective-C (iOS) and Java (Android) on the client.

5. Ably Realtime

Ably solves the most complex and demanding aspects of real-time engineering, making it easy for developers to power and scale real-time apps like chat, multiplayer games, real-time GPS location updates, IoT device control, and more. It also provides cloud infrastructure and APIs that help developers stream data between devices in real-time.

With over 40 Client Library SDKs and native support for more than six real-time protocols, getting started for any use case is fast and simple.

6. DeepStream

Deepstream is an open-source library for real-time web application development. The library, which is built with Node.js and Engine.io, helps developers build frontend web applications that perform real-time updates while requiring minimal backend code.

The Deepstream comes with a client library for the browser that lets the developer create and update data records on the fly. The client library relays updates to the server, which propagates the new data to other subscribed clients. The developer doesn’t have to write any specialized backend code to handle the changes or propagate the events.

7. Laravel-echo

In many modern web applications, WebSockets are used to implement realtime, live-updating user interfaces. When some data is updated on the server, a message is typically sent over a WebSocket connection to be handled by the client. This provides a more robust, efficient alternative to continually polling your application for changes.

To assist you in building these types of applications, Laravel Echo makes it easy to “broadcast” your events over a WebSocket connection. Broadcasting your Laravel events allows you to share the same event names between your server-side code and your client-side JavaScript application. It also supports several broadcast drivers out of the box: Pusher Channels, Redis, and a log driver for local development and debugging

Laravel Echo is a JavaScript library that makes it painless to subscribe to channels and listen for events broadcast by Laravel.


This article explores 7 useful JavaScript libraries that every developer interested in building real-time applications should know about. I hope it will help you pick up the right library for your next project.

Source: dev