Hello,
sgcWebSockets support Firemonkey, so yes, you can use in Android and iOS.
There is a component to connect to socket.io servers, so you will be able to connect to your socket.io server.
Chat, video, geofence... are not implemented by websocket protocol. WebSocket allows to send/receive text/binary messages. So, if you transmit video conferencing from socket.io server to your clients, client must read this data, decode and process. Of course, sgcWebSockets library doesn't know nothing about it.
Kind regards,
Sergio