Xabber is a XMPP Client for Android. Xabber is only able to provide connections to the Jabber Network and does that quite good. There is also a “Xabber VIP” App in store. BUT! Xabber comes without Ads. The VIP Version is just for supporting the developers. This APP is AD free.
ChatSecure is a encryption friendly Messenger, working with the XMPP Protocoll. There are a few comments raging about the lack of security and Filetransfers not working, but those problems are not App related. (Google does not provide SSL encryption via Gtalk, and filetransfers need a configured jabberserver to initiate the P2P Fileshare)
IM+ is a Multi Messenger which supports a wide range of protocols. Even Skype. But the free Version shows Ads which can lead to a problem on smaller phone displays. But it’s a quite good Messenger.