Real-Time Screen Sharing System (Android to PC)

A lightweight, high-performance screen sharing application using WebRTC and Node.js.

📁 Project Structure

screen-sharing-app/
├── public/
│   ├── sender.html      # Android Sender UI
│   ├── sender.js        # Android Sender Logic (WebRTC)
│   ├── receiver.html    # PC Receiver UI
│   └── receiver.js      # PC Receiver Logic (WebRTC)
├── server/
│   └── server.js        # Node.js Signaling Server
├── package.json         # Dependencies
└── README.md            # Setup Instructions

🚀 Local Setup (Windows 11)

1. Install Node.js: Download and install from nodejs.org.
2. Open Terminal: Navigate to the screen-sharing-app folder.
3. Start Server:

   npm install
   npm start

4. Access the App:
   • Sender (Phone): Open http://YOUR_PC_IP:3000/sender.html
   • Receiver (PC): Open http://localhost:3000/receiver.html

Note: Replace YOUR_PC_IP with your local IP address (find it by running ipconfig in CMD).

🌐 Global Access (VPS/Cloud)

To access this globally, you must use HTTPS as modern browsers (especially on Android) block getDisplayMedia on non-secure connections.

1. Deploy to VPS: Upload the folder to your server.
2. Setup SSL: Use Nginx with Certbot (Let's Encrypt) to serve the app over HTTPS.
3. TURN Server: For restrictive networks (mobile data), add a TURN server configuration in sender.js and receiver.js.
   • Recommended: Twilio Network Traversal Service or OpenRelay.

📱 Android 14 Specifics

• Works best in Chrome for Android.
• When you click "Start Share", a system popup will ask for permission to record/cast. Select "Entire Screen".
• Security: The browser requires HTTPS to enable screen capture APIs.

🛠️ Troubleshooting

• No connection? Ensure both devices are on the same WiFi for local testing.
• ICE Failed? This usually happens on mobile data. You will need to add a TURN server to the iceServers array in the JS files.
• Permission Denied? Make sure you are using https:// if not on localhost.