T-Mobile is the only big U.S. network that doesn't sell iPhones, but it welcomes customers who bought them elsewhere.
This week it announced that iPhones and other phones from rival networks will be getting high-speed online access in 14 cities, including New York, Boston, Detroit, Dallas, Philadelphia and Tampa.
T-Mobile promises savings for customers who move from AT&T, Sprint or Verizon by "unlocking" the software that binds their phones to those networks and signing them up for a T-Mobile plan instead. The ubiquitous advertisements show an open padlock with an iPhone in place of the lock body, making it clear who the target customer probably is. [See also: BYO iPhone to T-Mobile: How Much Can You Save? ]
But unlockers would lose something in exchange — data speeds — if not for T-Mobile's announcement that it is "enhancing" its coverage.
T-Mobile has mostly been a haven for iPhones from AT&T, since the networks have long used similar technologies. But all they had in common were the lower-speed "2G" data services that make anything beyond talking, texting and emailing excruciatingly slow.
Those 3G and 4G iPhones (and other models) get their high-speed access on the 1900 MHz frequency, which T-Mobile hasn't been supporting. But as of this week a T-Mobile spokesperson told TechNewsDaily it would provide 1900 MHz support.
With that, iPhone owners can get 4G data speeds in those cities (it was already available in a few other locations). T-Mobile claims that in its tests, an iPhone 4S got 70 percent faster data rates on its 4G network than the phone previously had gotten on the AT&T network. (The iPhone 4S is not technically a 4G phone, but T-Mobile has goosed the 3G network technology to provide higher speeds.)
These, of course, were T-Mobile's tests.
Starting with the iPhone 5, T-Mobile also can take models from Sprint and Verizon, but the company failed to clarify if those phones could now get 4G service. In an email to TechNewsDaily, the company wrote "Both Verizon and AT&T unlocked iPhone 5 devices are compatible with our network today and will receive 4G service as we retune our airwaves to turn on 4G service in our iPhone compatible spectrum in major markets this year."
There are several ways to get an unlocked iPhone. Apple sells iPhone 5 models starting at $649. Carriers will often unlock phones for customers at the end of the two-year contract. And customers can get software to unlock their phones themselves — but for a limited time.
In October, the federal government ruled that unlocking would no longer be exempt from the Digital Millennium Copyright Act (DMCA). People who want to jump to another network have to have bought their phone before January 26, when the exemption expires.
At least that's the current game plan. "Bear in mind this rulemaking isn't the final word on whether unlocking a phone violates the DMCA – arguably, locking phone users into one carrier is not at all what the DMCA was meant to do," said Mitch Stoltz, an attorney with the nonprofit Electronic Frontier Foundation. "It's up to the courts to decide."