The latest Opensignal report has revealed the mobile network experience of smartphone customers of Verizon, AT&T, T-Mobile US and Sprint.

The Opensignal bi-annual report analyzed the experience of U.S. user base of more than 1.6 million unique devices – during September 16 to December 14 –, spanning early adopter 5G through 3G.

Brendan Gill, CEO of Opensignal, said: “Our newest USA Report findings show that U.S. operators are investing across the board to improve the consumer experience, and that investment is paying off in faster speeds, lower latency and better video experiences.”

Users on AT&T’s network experienced 22 percent increase in download speeds from 22.5 Mbps to 27.5 Mbps. AT&T’s 4G customers achieved a download speed of 29.1 Mbps, which is 10.6 percent faster than its next competitor, T-Mobile, which records a download speed of 26.3 Mbps.

AT&T’s CTO took the right decision to make investment in LTE Advanced Pro network upgrades (5G Evolution) and incorporate technologies such as advanced carrier aggregation and 4×4 MIMO to improve customer experience.

T-Mobile had a score of 79.4 in voice app experience in the U.S. and AT&T had a score of 79.3. Voice app experience represents the quality of voice calls over communications apps such as WhatsApp, Skype or Facebook Messenger. Verizon and Sprint customers also experienced better voice app experience as the operators scored above 75.

T-Mobile US customers experienced 8.6 Mbps (+18 percent) upload speed. The jump from 7.3 Mbps in upload speeds is creating a bigger distance between T-Mobile and Verizon, which has been its primary competitor in this category. Verizon customers experienced 7.9 Mbps (+14 percent) upload speed.

Verizon received 95.9 percent rating for 4G availability, which is just slightly ahead of T-Mobile’s score of 95.4 percent. All four U.S. operators scored above 90 percent in the 4G availability category.

Verizon also won 4G coverage experience award with a score of 9.7 on a sale of 0-10. This metric measures how mobile subscribers experience 4G coverage on an operator’s network. Verizon is 0.4 points ahead of AT&T, which had a score of 9.3, Opensignal said.