AT&T, T-Mobile debut Windows Phone 7 devices

With the launch of Microsoft’s Windows Phone 7, two carriers, AT&T and T-Mobile USA, introduced three handsets that run on the new software, all of which are priced at about $200 with a contract. WP7-based AT&T phones are the Samsung Focus and HTC Surround. T-Mobile’s WP7 phone is the HTC HD7. Other WP7 phones waiting in the wings include the Dell Venue Pro and LG Quantum.

Microsoft is re-entering the mobile market at a critical juncture. Although the company needs traction, the popularity of Apple iOS products and the booming fortunes of Android-based phones act as an obstacle to adoption. WP7 offers an advanced media player, multitouch Web browser and touch-screen interface in addition to its more standard Windows features.