T-Mobile will begin in-store sales of both the Xperia Z from Sony and the Nokia Lumia 925 starting tomorrow.

Both smartphones fall under T-Mobile's no annual service contract concept. The Xperia Z will cost $99.99 down with 24 monthly device payments of $20. The Lumia 925 will cost $49.99 down with 24 payments of $20.

The Sony Xperia Z smartphone.

If a customer cancels wireless service with T-Mobile, the remainder of the device balance is due.

The Lumia 925 is the first LTE Windows Phone 8 smartphone that T-Mobile has sold. It features a 4.5-in. Pure Motion HD+ AMOLED display, with a 1280 x 768 resolution and weighs 4.9 ounces

It also runs a 1.5 GHz Qualcomm Snapdragon dual -ore processor and a 2000 mAh battery. The rear camera is 8.7 megapixels and the front camera is 1.2 megapixels.

The Xperia Z is water resistant and comes in either black or for a limited time, in purple. It has a 5-in. display at 1920 x 1080 pixels.

The Xperia Z runs Android 4.1 (Jelly Bean) and includes a 1.5 GHz quad-core Qualcomm Snapdragon S 4 processor. A 2,330 mAha battery helps support a 13-megapixel rear camera and a 2-megapixel front camera. It weighs 5.15 ounces. Access to a full spec sheet is posted on the T-Mobile web site.

This article, T-Mobile sales of Xperia Z and Lumia 925 start Wednesday , was originally published at Computerworld.com.

Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen or subscribe to Matt's RSS feed. His email address is [email protected].

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