New York (CNN Business) 5G is already here, but you can't do much to access those super-fast speeds unless you live in a specific place with a particular piece of technology. That's about to change.

Samsung and Verizon ( VZ jointly announced Monday the companies would sell a 5G smartphone in the first half of 2019. Although they didn't say which phone would support 5G , Samsung usually announces its latest Galaxy S smartphone in the spring.

The mystery phone may not be the first 5G smartphone to hit the market. Unsure of other companies' plans, Verizon and Samsung hedged by saying it would be "one of the first." But Samsung is by far the largest smartphone maker in the world, and its decision to launch a 5G smartphone means the rest of the market won't lag far behind. If smartphone companies want to stay competitive in the coming years, 5G will soon be a must-have.

That still doesn't solve the problem of network availability. Verizon's 5G network currently exists in only a small handful of cities. AT&T ( T ) also has 5G networks up and running in just seven cities. Sprint ( S ) and T-Mobile ( TMUS ) lag behind. Verizon and AT&T lack specific rollout plans or time frames, but they plan to bring many more cities online in 2019 and 2020. (CNN is owned by AT&T.)

Although 5G may not be much of a selling point now, it will be once it's pervasive enough. 5G promises much faster speeds than 4G. How much faster is up for debate (Verizon says "many times faster"), but lab tests have yielded speeds up to 100 times faster than 4G. When millions of people are on the network, though, that tends to slow speeds down a bit. Industry estimates put 5G at around 10 times faster than 4G in real-life scenarios.

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