Google’s prolific messaging client will be waved goodbye on the 16 February 2015, however, it appears to only be the Windows Google Talk desktop app that will be ending. Google has stated that the IM service will be wholly replaced by the Hangouts app, which is only available through using it’s Chrome browser.
The app will cease functioning, yet users will still be able to communicate with their contacts through Gmail, and third party applications by logging in with their Google details.
It’s unclear what impact services such as iMessage and WhatsApp have had on Google’s IM. Yet, with both of these services being relatively reliant on having a mobile device, it is unlikely that Google decision was motivated by competitors but rather an internal decision to unify the Google Hangouts brand.
Alternatives messaging clients through which you can access your contacts are apps such as Pidgin, Trillian and Adium as well as other Jabber-enabled clients.