updated 02:48 pm EDT, Tue March 26, 2013
Takes advantage of IPhone 5's wideband audio
The T-Mobile iPhone 5 will support the carrier's HD Voice technology, according to an announcement. The feature provides clearer voice calls when compared with normal cellphone service. To take advantage of it, though, all parties must be on a T-Mobile device, and connected to the carrier's HSPA, HSPA+, or LTE networks.
While T-Mobile won't be the only iPhone carrier with something like HD Voice, will be the only one in the US. When Apple launched the iPhone 5 last year it heavily promoted "wideband audio" as a feature. Only 20 carriers worldwide were announced as initial partners though, and AT&T, Sprint, and Verizon have yet to expose any plans for support.
The iPhone 5 is due to arrive on T-Mobile USA on April 12th. It will cost $100 up front, with further payments of $20 due each month for 24 months. The phone will come contract-free though, and with potentially cheaper monthly plans than offered by T-Mobile's rivals.