Hopefully you will have read and followed the code from the first part of this article. The first part covered most of base functionality including how to sign in, get the users details and get their contact list. What is left is how to actually carry out a conversation with a contact.
If you remember from the first article, in the signInCompleted event handler we defined three delegates to handle various events. The first part of this article talked about the first two of these delegates, and that leaves the last one to talk about :-