Following on from AT&T's announcement of the Lumia 520 appearing on their prepaid network GoPhone at the start of the week, MetroPCS (T-Mobile's prepaid department) are bringing the T-Mobile variant, the Lumia 521, into their stores today.

The new handset joins MetroPCS' expansion into fifteen new markets in the US, and takes place with AT&T's purchase of Leap Wireless, which focuses on 'unlimited service and no contracts', in the background. T-Mobile are hoping that any market instability will see them able to gain new customers, and is pushing Windows Phone to the underdeveloped pay as you go market in the US.

The Lumia 521 has the same hardware specifications as the Lumia 520, with support for the WCDMA 1700 (Band IV) and 1900 (Band II) frequencies. Other specifications include a 4.0 inch WVGA (800 x 480) TFT screen, 8GB of internal memory, microSD card support, a dual-core Snapdragon S4 processor running at 1GHz, and a 5 megapixel camera. but with slightly larger dimensions so accessories for the 520 and the 521 are not interchangeable.

The 520 handset range is easily the cheapest Windows Phone 8 device in the US. Couple that price with Windows Phone ability to run on lower spec hardware with the same smooth UI as the higher priced devices, and this is excellent value for money.