Google's instant messaging (IM) service, introduced in 2005. Google Talk provided text messaging and voice calling for Windows, Android, BlackBerry and Chrome OS devices. Based on the XMPP/Jabber protocol (see Jabber), Google Talk provided a link to the user's Gmail account and displayed the number of unread messages in the inbox. It was also a component of the Google Apps package (see G Suite). In 2015, the Google Talk client programs were discontinued although third-party apps that use the XMPP protocol are still supported.