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Историческую версию Talkonaut можно получить на Android
Talkonaut является клиентом Jabber с возможностью совершать голосовые звонки.
Talkonaut is a Jabber (XMPP) client with peer-to-peer voice calling over Jingle Audio extension. Talkonaut can be used with any Jabber account. Talkonaut supports a number of XMPP extensions including multi-user conference chat (XEP-0045), vCard based avatars (XEP-0153) and many others.
You can also use Talkonaut to make cheap voice calls to landline or mobile phone numbers through GTalk2VoIP infrastructure.