In brief: AT&T launched its low-band 5G wireless service in 28 additional US markets this week, pushing the total number of markets served to 355. With the additional markets, some form of AT&T's 5G service now covers 179 million consumers and businesses across the country.

Worth highlighting is the fact that we are talking about AT&T's low-band 5G wireless service which differs greatly from the ultra-fast high-band network that utilizes millimeter wave tech, or what most people typically think of when hearing the term "5G."

In testing AT&T's 850MHz 5G service several months back, Opensignal obtained an average download speed of just 59.3 Mbps which isn't much faster than 4G LTE.

AT&T's new 5G markets include Miami, Orlando, Austin, Dallas and Salt Lake City, among others. A full list of newly covered markets can be found over on AT&T's website.

AT&T said it has seen peak download speeds of over 2 Gbps with its 5G+ mmWave service. In independent testing, The Verge hit speeds north of 1 Gbps in the real world on Verizon's network.

Speed aside, the main difference between the two frequencies is in range. High-band mmWave service has an extremely limited coverage range whereas low-band frequencies can better blanket an area with coverage, at the expense of speed.

In either instance, you'll need a 5G-compatible phone to take advantage of the newer networks and those are still relatively few and far between at this point. That'll change over time as 5G network rollouts accelerate and the necessary radios come baked into smartphones as standard-issue hardware rather than a premium upgrade.

Image credit: TPROduction, Jonathan Weiss