Known as Bobsled, the T-Mobile app lets Facebook users place voice calls to any of their Facebook friends who are currently logged into Facebook Chat. T-Mobile claims that Bobsled is "one of the first VoIP seamlessly integrated into Facebook Chat" that can place calls to friends with just one click. Users can also use the app to leave voice mails for their Facebook friends and send them as either private messages or public messages posted on their Facebook walls.

OPEN LETTER:

Bobsled can be downloaded for free from Facebook and doesn't require a T-Mobile account to use. T-Mobile says it plans to add several features to Bobsled over the next few months, including video chat and "the ability to place VoIP calls to mobile and landline U.S. numbers." T-Mobile also wants to offer Bobsled applications for " and tablets across various mobile platforms, regardless of the carrier that powers such devices."

T-Mobile, the fourth-largest carrier in the United States, is in the process of being bought out by AT&T. If AT&T's T-Mobile acquisition gets approved by the Federal Communications Commission, it will create by far the largest carrier in the United States with in excess of 130 million wireless subscribers. The proposed merger would also be the fourth major wireless carrier merger in eight years, following AT&T-Cingular in 2004, Sprint-Nextel in 2005, and Verizon-Alltel in 2008. AT&T would also become by far the largest wireless carrier in the United States with more than 130 million subscribers.

in Network World's LANs & Routers section.