How to Build a Messaging App Like Telegram

Messaging applications have become a ubiquitous part of our everyday routines, enabling us to maintain connections with our loved ones, colleagues, and social circles. One of the most popular messaging platforms is Telegram, known for its robust features and emphasis on privacy. If you're interested in creating your own messaging app, you've come to the right place.

In this article, we will guide you through the process of building Telegram alternatives. We'll cover the essential features, technical requirements, and best practices to ensure your app stands out in the crowded messaging market. Whether you're a budding entrepreneur or an experienced developer, this step-by-step guide will provide you with the tools and knowledge needed to bring your messaging app idea to life.

Step-by-step Guide on How to Build a Messaging App Like Telegram

Building a messaging app with robust, real-time capabilities like Telegram requires using a powerful SDK and managing multiple components such as user authentication, real-time messaging, and media handling. Using ZEGOCLOUD’s SDK, you can efficiently develop a high-quality messaging app with essential features like instant messaging, voice and video calls, media sharing, and more.

Here’s a step-by-step guide to help you get started:

Prerequisites

Before beginning, ensure you have the following set up:

• Sign up for a ZEGOCLOUD developer account and access to your AppID and server credentials.
• Node.js installed on your machine.
• Basic knowledge of JavaScript or TypeScript.
• A code editor like Visual Studio Code.
• A WebRTC-compatible browser (e.g., Chrome, Firefox).

1. Set Up the Project

Create a project folder and initialize a Node.js project. This structure will hold your app’s core files, including HTML for the user interface, JavaScript for business logic, and CSS for styling.

mkdir telegram-clone
cd telegram-clone
npm init -y

Project Structure

Inside your telegram-clone folder, create the following basic file structure:

telegram-clone/
├── index.html      # User interface for the chat
├── index.js        # Business logic for messaging and calling
├── styles.css      # Basic styles for the chat interface
├── package.json    # Manages dependencies and project metadata

2. Build the HTML User Interface

In index.html, define a simple layout with areas for chat, contacts, and media controls. This includes input fields for sending messages, a video container for video calls, and buttons for toggling camera, microphone, and call controls.

Example: Basic HTML structure for the messaging app

mkdir telegram-clone
cd telegram-clone
npm init -y

• zego-express-engine-webrtc: Manages video calling and media functionality.
• zego-zim-web: Handles real-time messaging (ZEGOCLOUD Instant Messaging SDK).

4. Import and Initialize the SDKs

In index.js, import ZEGOCLOUD’s SDKs and initialize them with your AppID and server details.

telegram-clone/
├── index.html      # User interface for the chat
├── index.js        # Business logic for messaging and calling
├── styles.css      # Basic styles for the chat interface
├── package.json    # Manages dependencies and project metadata

5. Configure Messaging Functions

Next, configure functions to manage sending and receiving messages. ZEGOCLOUD’s ZIM SDK enables sending text messages in real-time.

Login to ZIM (Messaging)

Start by logging the user into ZIM for messaging. Replace the token and userID with actual credentials as needed.

    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Telegram Clone</title>
    <link rel="stylesheet" href="styles.css">


    <div>





<h3>
  
  
  3. Install ZEGOCLOUD SDKs
</h3>

<p>To enable real-time messaging and video call functionality, install the required SDKs via npm.<br>
</p>

<pre class="brush:php;toolbar:false">npm install zego-express-engine-webrtc zego-zim-web

Send Messages

Define a sendMessage function that will send messages to a selected contact or group. The message will be displayed in the chat interface.

import { ZegoExpressEngine } from 'zego-express-engine-webrtc';
import { ZIM } from 'zego-zim-web';

// Replace with your actual AppID and server URL
const appID = 123456789; 
const server = 'wss://your-server-url';

const zg = new ZegoExpressEngine(appID, server); // For video calls
const zim = ZIM.create({ appID }); // For messaging

Receive Messages

Set up an event listener to receive and display incoming messages from other users.

async function loginZIM() {
    const zimUserID = 'user_' + new Date().getTime();
    const zimToken = 'your_zim_token_here'; 

    await zim.login({ userID: zimUserID, userName: 'User' }, zimToken);
}

6. Set Up Video Call Functionality

To support video calling, use the ZegoExpressEngine SDK for initializing, managing, and controlling video streams.

Initialize Video Call

In index.js, create a function to set up and start a video call. This function handles the login process and streams management for local and remote video.

async function sendMessage() {
    const messageInput = document.getElementById('message-input');
    const messageContent = messageInput.value;

    await zim.sendMessage({
        conversationID: 'chat-id',
        conversationType: ZIM.enums.ConversationType.P2P, // For one-on-one chats
        message: { content: messageContent }
    });

    displayMessage('You: ' + messageContent);
    messageInput.value = ''; // Clear input field after sending
}

function displayMessage(message) {
    const messagesContainer = document.getElementById('messages');
    const messageDiv = document.createElement('div');
    messageDiv.textContent = message;
    messagesContainer.appendChild(messageDiv);
}

7. Add Call Controls

Define buttons and functionality for muting, unmuting, and ending calls.

zim.on('receiveMessage', (msg) => {
    const messageContent = msg.message.content;
    displayMessage('Friend: ' + messageContent);
});

8. Implement Cleanup Functionality

Add a cleanup function to properly log users out from ZIM and ZegoExpressEngine, ensuring resources are freed.

const localVideo = document.getElementById('localVideo');
const remoteVideo = document.getElementById('remoteVideo');

async function startVideoCall() {
    const userID = 'user_' + new Date().getTime();
    const token = 'your_video_token_here'; // Replace with your token

    await zg.loginRoom('room-id', token, { userID, userName: userID });

    const localStream = await zg.createStream();
    localVideo.srcObject = localStream;

    zg.startPublishingStream('streamID', localStream);

    zg.on('roomStreamUpdate', async (roomID, updateType, streamList) => {
        if (updateType === 'ADD') {
            const remoteStream = await zg.startPlayingStream(streamList[0].streamID);
            remoteVideo.srcObject = remoteStream;
        }
    });
}

startVideoCall();

9. Style the App

Create styles.css to add basic styling for the chat interface.

function setupCallControls(localStream) {
    const toggleCamera = document.getElementById('toggleCamera');
    const toggleMic = document.getElementById('toggleMic');
    const endCall = document.getElementById('endCall');

    let isCameraOn = true;
    let isMicOn = true;

    toggleCamera.onclick = async () => {
        isCameraOn = !isCameraOn;
        await zg.mutePublishStreamVideo(localStream, !isCameraOn);
        toggleCamera.textContent = isCameraOn ? 'Turn Off Camera' : 'Turn On Camera';
    };

    toggleMic.onclick = async () => {
        isMicOn = !isMicOn;
        await zg.mutePublishStreamAudio(localStream, !isMicOn);
        toggleMic.textContent = isMicOn ? 'Mute Mic' : 'Unmute Mic';
    };

    endCall.onclick = async () => {
        await zg.destroyStream(localStream);
        await zg.logoutRoom();
        zg.destroyEngine();
    };
}

Conclusion

You've made it through the step-by-step process of building a messaging app like Telegram. This has been an ambitious project, but with the help of powerful tools like ZEGOCLOUD's SDKs, you now have the core features and functionality in place.

Think about how far you've come - you designed an intuitive user interface, set up real-time messaging, enabled video calling, and integrated media sharing. ZEGOCLOUD took care of the technical complexities in the background, allowing you to focus on crafting an amazing user experience.

Whether this was a personal project or you're aiming to launch a commercial messaging service, you now have a solid foundation to build upon. As your user base grows, ZEGOCLOUD's scalable platform will ensure your app can handle the increased demand without any hiccups.