How do chat iOS applications communicate?

Question

How do text chatting in applications like Whatsapp and Skype communicate? Specifically, how are messages received real time?

Thanks in advance!

Answer 1

This is related with what is called Socket programming in iOS. you may refer to apple developer documentation for that or this link can help you regarding this.

Following links infact would be very helpful:

http://blog.scriptico.com/08/iphone-chat-native-rtmp-library-for-ios-in-action/

http://mobile.tutsplus.com/series/building-a-jabber-client-for-ios/

Whatsapp which uses XMPP also based upon socket programming.

Thanks