The United States and South Korea are the countries most strongly linked with the earliest widespread roll-outs of the new mobile data-transfer standard, 5G. AT&T is one of the US networks engaged in the upcoming national 5G distribution program. However, reps from the carrier have warned against getting too excited about it right now.
https://www.notebookcheck.net/5G-is-not-all-it-s-cracked-up-to-be-yet-AT-T.362031.0.html