Ookla, creators of the Speedtest.net broadband test, compiled data from tests run by iPhone customers using the Speedtest.net app on both AT&T and Verizon. On average, reported AT&T iPhone transfer rates were roughly two times faster than the Verizon iPhone's.

The AT&T iPhone's average download speed was 1,769 kbps, and the average upload speed was 730 kbps. By way of comparison, the Verizon iPhone's average download speed was 848 kbps, and the average upload speed was 506 kbps.

The results come from 43,000 AT&T iPhones and 14,000 Verizon iPhones all over the United States. Most Speedtest.net app users ran the tests multiple times, totaling 106,000 results from AT&T iPhone users and 49,000 results from Verizon iPhone users.