The main aim is to have a fully functional single conversations feature. You might think it's not much, but by fully functional I mean having those single conversation built on top of an almost complete core of the app. So we'd have notifications, settings interface, chat logging, connection monitoring, delivery statuses, presence updates, contacts management and others.

Having those things stuff built correctly and tested would allow most of the focus afterwards to be directly on more chat-related features (group chats, sending media..etc).