More complete run-through here - http://www.behance.net/gallery/Gchat-concept-iOS-app/7256351
(sorry for taking off-site!)
Here's a preview of how I imagine the functionality of conversation mode to go; when in chat you can swipe up from the bottom of the screen to bring up the an 'Editing' tab bar. Here is where you can share photo/location, edit the conversation by deleting specific messages, add other contacts to the conversation, go off the record or block users (similarly to edit mode, to block users you have a popover on their avatar so if in group chat mode you can block multiple users).
Let me know your thoughts and thanks for checking it out!
Don't forget to check out the @2x :)
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