Samsung's new Galaxy S8 and S8+ will get access to faster speeds on AT&T's network in more than 20 cities by the end of the year, the carrier announced on Tuesday.

The speed boost is made possible by something that AT&T is referring to as "5G Evolution"—it's not a true 5G network (that's still years away), but thanks to improvements in the way it manages its existing cell network, AT&T is able to promise speeds up to twice as fast as users currently experience.

The faster speeds are now available to subscribers with the Galaxy S8 and S8+ in parts of Austin. By the end of the year, the service will expand to Atlanta, Boston, Chicago, Los Angeles, Indianapolis, Nashville, and San Francisco, among other cities. It will also eventually be compatible with other devices beyond Samsung's flagships, although AT&T didn't say which ones.

Assuming you live in one of the aforementioned cities and use a compatible device, you could see improvements like reduced lag while playing internet-connected mobile games and less buffering for streaming video.

Back in February, AT&T offered a glimpse of the software improvements that makes the speed boost possible. Known as software-defined networking, the open-source code enables engineers to treat the AT&T network as if it were a giant data center, remotely changing server configurations to optimize data flows without having to send technicians out into the field with trucks and ladders. Thirty-four percent of the network can be managed this way today, AT&T executives said, and they plan to have it manage 75 percent by 2020.

Like other carriers, AT&T is also working on building and testing a true 5G network. In addition to improving internet speed for smartphones, the 5G standard could also be used to replace DSL connections for in-home internet.