ooVoo
A free service that provides instant messaging, phone calling, video messages and video chatting with up to twelve other users. First released in 2007, ooVoo currently has more than 46 million registered users and is available as a platform-independent Web client as well as for Microsoft Windows and Mac OS X operating systems and Google Android and Apple iOS mobile platforms.
ooVoo also recently released a Facebook app that functions similar to Google Hangouts, enabling Facebook users to take part in group video chats. While Facebook has its own video chat feature, the Facebook Video Calling app currently only supports one-to-one video chats.


