In Q1 and Q2, Speedtest users ran more than 12 million mobile network speed tests on more than 2.8 million mobile devices. The company's US Mobile Performance Report indicated that T-Mobile is the fastest overall carrier, retaining its crown from last year. Verizon was second, with AT&T and Sprint third and fourth. However, Verizon was the fastest in 45 out of the top 100 most populated cities and Washington, DC. T-Mobile took the crown in 33 locales, AT&T in 12 and Sprint won in only five cities.

The data might be illuminating (or disappointing) for those in Laredo, Texas; Anchorage, Alaska; Madison, Wisconsin; Reno, Nevada; and Lubbock, Texas. Ookla says those had the slowest mobile speeds among the cities it looked at. Downloads in Laredo averaged a relatively sluggish 18.52 Mbps. However, these are all more rural cities, with infrastructure that pales next to the country's metropolises. They'll likely see a significant speed boost when 5G mobile connectivity rolls out starting next year.