RCS hasn't conquered the world just yet, but Google is winning the war. Earlier this year, T-Mobile announced that it was switching to Google's RCS messaging and app as the default for devices on its network, and now AT&T has revealed that it is also following suit. There's no firm schedule yet, but future AT&T devices, including Samsung phones, will ship with Google Messages as the default messaging app — and, if AT&T will finally adopt the Universal Profile standards and interconnect to other networks, customers can finally enjoy the perks of improved RCS messaging with out-of-network friends.

In case you aren't familiar, RCS Messaging is basically an enhanced and decentralized SMS-replacing standard that allows for richer and higher quality media, read receipts, group chats, and Wi-Fi-based messaging, among other features. While it's a messaging system that can work between networks thanks to the Universal Profile standards, most carriers spent the last few years trying desperately to lock customers into their own closed-off non-interconnected versions — in short, defeating the whole damn purpose. Thankfully, Google rolled its own system right into the Messages app, cutting the carriers out of the equation entirely. "Chat," as Google's RCS system is called in the Messages app, is now available worldwide, including end-to-end encryption for one-on-one messages.

Today's news about AT&T news comes from a joint announcement between the company and Google and follows the death of the prior RCS venture between the US carriers. Announced back in 2019, that cross-carrier compatibility effort died just this spring after several unfruitful years on the vine following T-Mobile's announcement that it was using Google Messages and RCS. This latest news means two out of the three big US carriers are now using Google Messages as their default RCS messaging apps, leaving only Verizon behind. (Though we should point out: Pixels on Verizon's network do connect to Google's Jibe for RCS — this is a terribly complicated subject.)

The Verge's Dieter Bohn has also confirmed that the change will include Samsung phones on AT&T as well. Though the S21 series shipped with Google Messages in other markets, the US versions still use Samsung's app until now.

There are a few last technical details in today's announcement that aren't certain. It isn't clear if AT&T is simply switching to Google's Jibe network via the Messages app for RCS, or if AT&T is finally adopting a proper Universal Profile-based implementation of its own with a Jibe interconnect — the Messages app can work with both, though the user-facing effects would be about the same. We've reached out to AT&T for more detailed information.

Update: We're told that AT&T's network will continue to toll its own RCS implementation with the Messages app connecting to that backend, though that answer doesn't quite make sense to us. See, Google Messages will only connect to a carrier's RCS system if it's Universal Profile-compatible, and to date AT&T's implementation hasn't been. Either AT&T's network is being updated to interconnect with other RCS networks and fully meet Universal Profile standards, or Google Messages is going to continue to connect through Jibe for AT&T customers when the change happens, in contradiction to what we've been told.

We've asked for additional information, we'll let you know if we hear more. But either way, that should mean customers on AT&T should be able to enjoy cross-carrier RCS with their default messaging app in the future.