Google's Advanced Technology And Projects group (ATAP) in charge of Projects Ara and Tango, recently transferred to Google after the sale of Motorola Mobility to Lenovo, has the best motto ever (at least when it comes to divisions in large, publicly traded companies).
Chat clients limited to one-on-one conversation are going the way of the dodo. We've got numerous options for group messaging including: Facebook Messenger, WhatsApp, Google+ Messenger, Live Messenger, and we're even pretty sure Babel (or whatever it will be called) will join the list. Today, popular cross-platform chat app, Tango, steps up to match its competitors.
The additions to the interface are very straightforward. You can pick multiple people from your contact list to start a conversation and at any time add new people or leave the chat altogether from the participants screen.