T-Mobile introduced Bobsled, a calling feature integrated into Facebook chat that lets users call one another for free, as well as leave private and public voice mails. (Technologizer).

移动电话运营商t - Mobile特别针对Facebook聊天功能开发集成通话应用，用户利用Bobsled插件便可免费畅聊，并接收私人或公开语音留言。

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As the leader in group video-chat, ooVoo's new mobile apps are the only major communications product offering users four simultaneous video streams at once on mobile devices, and hosting a total of up to 12 participants on one call, for free!

ENGADGET: ooVoo updates its iOS and Android apps to support four-way video calls