A survey of the cell phone service in Chicago, USA found that thanks to the strong results on Verizon's LTE network, it received the highest combined score of 89.4 out of a possible 100. Sprint (49.5) and AT&T (45.3) had a statistical tie for second place.
The survey was carried out by RootMetrics which installs an application into smartphones of participating users to measure network performance.
To evaluate the Chicago market (defined as the Chicago Urbanized area according to the U.S. Census Bureau), RootMetrics performed thousands of call, data and text tests during a seven day period, covering all hours of the day and night, in April 2011. The tests centered on activities that consumers perform most often: making phone calls, uploading and downloading files from the Internet, and sending and receiving texts. It's important to note that during the testing period, Verizon's LTE network experienced an outage on April 27. As network outages impact consumer experience, RootMetrics included results of the outage in its findings.
Even with the network outage factored in, Verizon's LTE network delivered the fastest data speeds in the area. RootMetrics recorded download speeds on average nearly 3 times faster than the second-fastest download network (Sprint) and 4 times faster than the second-fastest upload network (T-Mobile). During data collection, RootMetrics found that AT&T's network was the most reliable, successfully connecting to the data network nearly 97 percent of the time. Chicagoans on T-Mobile's network may experience more trouble, as RootMetrics measured a data success rate of only 76 percent.
During the measurement, RootMetrics experienced failed calls on T-Mobile's network eight percent of the time, over four percent of the time with AT&T, just over one percent of the time on Verizon and less than 0.5 percent of the time on Sprint. Compared to other markets measured (Seattle, Dallas, Miami, Washington, D.C.), dropped calls rates in Chicago were relatively low. No carrier measured dropped calls more than two percent of the time.
Average text delivery times amongst the four carriers ranged from 13.5 seconds (T-Mobile) up to 25.3 seconds (Sprint). T-Mobile's network delivered texts to customers within its own network between two times to eight times faster than other carriers.