XMPP JabberClient is an open source XMPP and Jabber instant messaging client for Android.  XMPP Jabber Client is a amazing free and open source client for android. XMPP Jabber Client enables you to connect to an XMPP for instant messaging with other people over the Internet. 

Pros & Cons :  

I use this client from last year. It’s a nice client for nimbuzz chatting. Although it does not support all required features, but it cover most of the features.

PROS : 

• Multiple Accounts
• Exceptional battery life
• Contact Avatars
• Various forms of end-to-end encryption
• Photo transfers
• Conferences chats
• Many more!

Most loving feature of this app is multiple account and exceptional battery life. Once you make online your id, it remains online for the most of time ( My id remains online for more than 6 months). At anytime if internet disconnected due to signal issue ,  ID automatically connected & online. Once you join a conference, if you can’t reply, your I’d kicked & it again join automatically. It means You can make hang bots with this app ;).

CONS :

• In conference, you can’t moderate user with owner / admin / ban  etc.
• Can’t find users list in a conference.
• Can’t find online users.

Download Link : https://play.google.com/store/apps/details?id=com.KDJStudios.XMPPJabberClient