Bobsled's Facebook page

The new app is a download that Facebook Chat users can add to their browsers to chat with their friends. It also allows users to leave voice messages on each others’ walls, T-Mobile said in a blog post. Those messages can be either public or private.

According to T-Mobile’s press release, you don’t have to download the app to receive calls.

The post says users don’t even have to dial to call their friends; a single click on his or her name will place a call. Calls are free regardless of location.

Right now, the app can only make calls through Facebook, but T-Mobile wrote that it will eventually support video calls, calls to landline and mobile phones, and applications for smartphones and tablets, regardless of carrier.

(Post Co. Chairman and Chief Executive Donald E. Graham sits on Facebook’s board of directors, and the newspaper and many Post staffers use Facebook for marketing purposes.)

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