Since I am posting about a lot of secure messaging systems, TextSecure has a new version out (I’m not sure if it is out for iOS yet), but this feature looks great:
The new TextSecure also introduces support for private group chat. Users can now create groups with a title and avatar icon, add their friends, join or leave groups, and exchange messages/media, all with the same end-to-end encryption properties pairwise TextSecure chats provide.
In fact, TextSecure is probably the most robust and full featured. Glad there are so many options.