The promise of faster mobile service is finally getting on the map later this year -- and it's headed south.

AT&T announced late Tuesday it will first roll out 5G to three locations: Dallas, Texas; Waco, Texas; and Atlanta.

The wireless giant previously said it would introduce the service to about a dozen U.S. markets by late 2018, but it didn't specify which cities or a specific timeline. The company said it would announce more cities in the coming months.

5G, heralded as the next generation of wireless network technology, is about 10 times faster than 4G, according to experts. That's enough to download a 3D movie in 30 seconds. It would take six minutes on 4G.

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But don't get too excited. You'll need a 5G capable mobile device to access the network, and currently, there are no compatible smartphones.

AT&T (T) said it expects devices from different phone makers to hit the market this year, and it plans to add to its lineup in early 2019.

5G will likely have the biggest impact on businesses. 5G networks will be able to power self-driving cars, virtual reality and smart cities. It could lead to new surgical procedures, safer transportation and faster communication with first responders.

Related: What is 5G?

Last year, Verizon announced it would launch 5G residential broadband services in 2018 in select markets.

While AT&T and Verizon have made some strides with 5G, experts project these networks will launch in 2020. Even if a 5G network is rolled out this year, essentially no one will be able to take advantage of it until 5G-enabled devices hit stores.

(AT&T has agreed to buy Time Warner, the parent of CNN, TNT, HBO, and other channels and websites.)

-- CNN's David Goldman contributed to this report.