Android Chatting App (XMPP)

I want to build a chat app. The goal is to connect with strangers and chat. Before connecting with a stranger the user can choose a topic of conversation (user will input two to three words). Other users will see list of topics to choose from to converse about. When they choose the topic then they will connect with the original person to chat. We will need chat tools like profile and buddy list. Let me know if I'm forgetting something obvious. I will provide two versions of UI. Initial wireframe then final.