What is the best technology to use to transfer data between server and android/ios in real time?

Question

Mobile development

What is the best technology to use to transfer data between server (spring-boot) and android/ios in real time: socket, websocket, socketio, long-polling, etc.. ?

Answer 1

WebSocket is better than long-polling for "real time", it's a full-duplex connection.
Besides,

Socket.IO primarily uses the WebSocket protocol with polling as a fallback option, while providing the same interface. Although it can be used as simply a wrapper for WebSocket, it provides many more features, including broadcasting to multiple sockets, storing data associated with each client, and asynchronous I/O.

If we are talking about a client-web browser, then you can still use Server-Sent Events (SSE).