Google refuses support of XMPP
For many years, Google Talk worked on the basis of the XMPP protocol, including supporting XMPP Federation with other networks and making it possible, for example, to use ICQ through the appropriate jabber transport in Google Talk (both in the application and in chat in Gmail via the web).
However, when switching to Google Hangouts, presented at the last Google I / O conference, which combines Google Talk and Google+, Google refuses to support XMPP. The Google Talk Android app is automatically updated on Google Hangouts. Chat in Gmail so far can be switched to Hagouts and back to the classic look (respectively, communication with jabber clients of other networks and contacts of ICQ and other transports is possible only in the latter case).
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However, when switching to Google Hangouts, presented at the last Google I / O conference, which combines Google Talk and Google+, Google refuses to support XMPP. The Google Talk Android app is automatically updated on Google Hangouts. Chat in Gmail so far can be switched to Hagouts and back to the classic look (respectively, communication with jabber clients of other networks and contacts of ICQ and other transports is possible only in the latter case).
[one]