To use the XMPP/Jabber service, you need to install and use XMPP client.
XMPP is open standard protocol, so there are many kind of clients.
This page attempt to give recommended desktop application of XMPP clients.
Psi is cross-platform XMPP client that compatible with Windows, Linux and MacOS.
See following guide for installing Psi on Windows.
Audium is a popular XMPP client for Mac users.
These are recommended XMPP clients for mobile
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