T-Mobile has just announced its new ‘unlimited and unlocked iPhone’ plans, bringing confirmation that T-Mobile is upping its support for the iPhone.

T-Mobile is the only US carrier not to offer the iPhone, however it claims that over 1 million of its customers do use the device. For many years those users have suffered the horror of operating on Tmo’s 2G EDGE data service (which is significantly slower than the 3G and 4G speeds offered by its rivals) because T-Mobile uses the AWS spectrum for 3G data, a frequency not supported by the iPhone.

T-Mobile has been increasing its 4G HSPA+ service that operates on the 1900MHz frequency, this is supported by the iPhone, and is part of T-Mo’s plans to switch over to LTE.

Alongside this push, T-Mobile has recently launched a marketing campaign that claims users will save over $50 a month by switching their unlocked iPhones to T-Mobiles unlimited data plan, rather than one of AT&T’s puny tiered plans.

These phones will have to be unlocked, so if you don’t own an iPhone already, you’ll have to buy one directly from Apple, which will probably put a rather large dent in the $1200 you’ll have saved over the period of a 2 year contract. T-Mobile’s employees will shortly begin training in the art of iPhone set up, and T-Mobile is developing iOS versions of its my Account, Visual Voicemail and TV apps.

This is a huge step forwards for T-Mobile, and one that will definitely help push them in forwards in terms of customer base, however, they will still be lagging behind the big guns. What are your thoughts on this development?

@TiP_Stephen