Open source Jabber/XMPP client that is free for Android. It is easy to use and reliable. Built-in support for group chats, images and e2e encryption. Design principles Make it as easy as possible to use the conversation.im server. After a 6-month trial, the annual cost for that server is 8 euros. But Conversations can be used with any other XMPP servers. Many XMPP servers run on volunteers, and many are completely free. XMPP Features conversations works on every XMPP Server. XMPP, however, is an extensible protocol. These extensions can also be standardized in so-called XEPs. These extensions are supported by Conversations in order to improve the user experience. These extensions may not be supported by your current XMPP Server. To get the best out of Conversations, you can either switch to an XMPP Server that supports these extensions or - even better – run your own XMPP Server for yourself and your friends. The XEPs that are currently available include XEP-0165: SOCKS5 Bitestreams or mod_proxy65. If both of the parties are behind firewalls (NAT), this will be used for file transfers. XEP-0163 Personal Eventing Protocol (for avatars) XEP-0191 Blocking command allows you to blacklist spammers and block contacts, without having them removed from your list. XEP-0198 - Stream Management allows XMPP the ability to withstand small network outages or changes in the underlying TCP connections. XEP-2280: Message Carbons, which syncs your messages to your desktop client automatically. This allows you to seamlessly switch between your mobile client and your desktop client within one conversation. XEP-237: Roster versioning is used to reduce bandwidth when using poor mobile connection. XEP-313: Message Archive Management synchronizes message history with server. You can catch up on messages sent when Conversations was offline. The server can detect whether Conversations are running in the background by using XEP-352 Client State Indication. This allows the server to withhold unimportant files in order to reduce bandwidth. The HTTP File Upload component of XEP-363 allows file sharing in conference calls and offline contact. This component requires an extra component to your server.