Proving which phone carrier is the best can be a difficult endeavor to take up, and sometimes you need a bit more than anecdotal evidence.
Commercials featuring big floating blue and red maps help a little, but that story about how you couldn't eat at that one restaurant in Nowheresville, Calif., because you couldn't load up your Groupon on your smartphone helps even less so.
If the name RootMetrics looks familiar to you, it might be because you've seen its interactive coverage map included in every one of our cell phone reviews.
"We're really all about consumer advocacy," said Bill Moore, CEO and president of RootMetrics. "We do exactly what consumers do," in terms of testing the performance of major carriers.
Instead of making calls in a lab setting with lab equipment, Moore told CNET, RootMetrics traveled to more than 50 cities and used off-the-shelf phones to download files, make calls, and send texts.
Tests were held indoors, outdoors, and while driving in a car (in total, more than 103,000 miles were driven during the course of this year's testing). For every carrier, the higher-end, best available phones were chosen for testing to "show the network in the best light," Moore said.
Carriers were rated on four categories per city: data, calls, texts, and overall performance. To see who came out on top (and who was subpar), read on.
When Verizon entered the 4G race, it sprinted ahead early and aggressively, and it hasn't looked back since. That's why it was no surprise that Big Red was dubbed the top data carrier. Not only was Verizon the first national carrier to launch an LTE network, but its speeds "were often as fast or faster than the maximum speeds delivered by the other carriers," according to the review.
The data tests measured how quickly each carrier's network was able to download and upload files, and how often a user could access a carrier's data network successfully. In San Francisco, for example, Verizon's average upload speed was nine times faster than T-Mobile's, 11 times faster than AT&T's, and 14 times faster than Sprint's. Furthermore, the carrier's maximum download and upload test speeds in the city were 43Mbps and 24.9Mbps, respectively. Across all of RootMetric's test markets, Verizon's LTE data download speed was 11.3 MBps.
That's not to say other carriers were blasted out of irrelevant oblivion. In the later part of 2011, T-Mobile pulled some impressive numbers on its upgraded HSPA+42 network. The fact that speed rates on this network, which isn't even official 4G technology, were able to compete with other carriers is no small feat. In cities that had its HSPA+42 coverage, T-Mobile ranked above AT&T and Sprint, and their download speeds jumped significantly after introducing devices capable of handling the network.
Meanwhile, as T-Mobile won the unofficial title for "most improved," AT&T distinguished itself as "most consistent." According to the report, when a "carrier's upgraded network is unavailable, your speeds dip as you drop to one of the carrier's older infrastructures." In the case of AT&T, when its upgraded network became inaccessible, data speeds did not drop so severely because of the carrier's robust infrastructure.
Sprint, on the other hand, did not fare so well. Wherever WiMAX was unavailable, the carrier's speed was sluggish and in 13 out of the 50 test cities, Sprint's average download speed dropped below 1Mbps. In cities that did not have LTE at the time, Verizon was the only other carrier that went below the 1Mbps mark, too.
To rate call performance, RootMetrics measured how many times a network either dropped a call or was unable to place an outgoing call, within its own network, as well as outside its network.
Because all four major carriers gave such stellar performances, the report declared everyone a winner for its call category (which is just another way of saying no one won, really).
If you're dying to know who had the slight edge, RootMetrics suggests you could look to Verizon and Sprint--but the gap between the best and "worst" performers was so small, there really was no use to spout about a carrier's general call performance.
Instead, consumers should be more concerned with how well a carrier can make calls in specific locations. To compare how well carriers hold up in your neighborhood, check out RootMetrics CoverageMapp app.
For those who are concerned with superb texting speeds, RootMetrics conducted a series of tests to see how long it took each carrier to send or receive a text message. In this category, T-Mobile scored the highest. In San Francisco, for example, it took T-Mobile an average of 8.4 seconds to send a text--nearly twice as fast as Verizon and Sprint. AT&T also did well throughout the year for sending and receiving texts.
Verizon and Sprint were major disappointments, however, as they clocked in with the slowest text speeds. According to the report, when delivering a text within its own network, Sprint lagged especially behind and trailed the other carriers by a wide margin.
In the end, Verizon came out on top, as it seemed that no one could touch its lightning-quick LTE network. But with carriers always upgrading their networks, and RootMetric's plans to cover 100 more cities in 2012, Verizon's lead could vanish before we know it.
Even Moore, who emphasized that AT&T and T-Mobile are rapidly improving their networks, cautioned consumers that carrier performance is always evolving.
"We can see that the speed race was dynamic in 2011," Moore said. "But it's likely to become even more dynamic in 2012, and even more so with newer technologies after LTE."
Editors' note: This post was updated January 31, 2012, at 2:13 p.m. with additional information.