ChatXmpp is an Android app that allows you to connect to chat services such as Gtalk. This app allows you to configure your status, status message, and avatar as much as you want. It also allows you to add and remove contacts. Aside from that, it can also load and show your friends' avatars through the use of VCard.

Chat for Google Talk and Xmpp also provides chatroom support. You can also access your chat history using this app. It can also keep the app running in the background and receive notifications when new messages arrive.

Take a look at this Android app that uses the XMPP protocol.