TokBox alternatives

TokBox
TokBox provides a free API that allows anyone to add group video chat features to their own websites. Experienced programmers use the OpenTok API to build custom interactive video chat applications. More casual users can download OpenTok plug-n-play apps that provide the same group video chat capability when users drop them into their personal blogs or websites.
TokBox alternatives are:
Skype, ooVoo, TinyChat, WebEx, iMessage