Are sockets used for network data exchange in iOS applications?

Yes, sockets are used in iOS applications to implement network data exchange, especially when maintaining a persistent connection or real-time communication is required (e.g., chats, games, streaming).

To work with sockets in iOS, you can use:

• BSD sockets via low-level API.
• High-level libraries, such as Starscream for WebSocket.
• Network.framework, which supports TCP/UDP connections and a more modern approach to network interaction.

Example of using WebSocket with Starscream:

import Starscream

class WebSocketManager: WebSocketDelegate {
    var socket: WebSocket!

    init() {
        var request = URLRequest(url: URL(string: "wss://example.com/socket")!)
        socket = WebSocket(request: request)
        socket.delegate = self
        socket.connect()
    }

    func websocketDidConnect(socket: WebSocketClient) {
        print("Connected")
    }

    func websocketDidDisconnect(socket: WebSocketClient, error: Error?) {
        print("Disconnected")
    }

    func websocketDidReceiveMessage(socket: WebSocketClient, text: String) {
        print("Received text: \(text)")
    }

    func websocketDidReceiveData(socket: WebSocketClient, data: Data) {
        print("Received data")
    }
}

Thus, sockets are a common and effective way of network communication in iOS.