It's and android and iphone app for video chat. Kinda like Qik and Facetime except it can cross the android-ios divide.
Knocking Live Video Broadcasting Cross Platform App for iPhone and Android Mobile Phones
http://androidforums.com/htc-evo-4g/144105-knocking-live.html
Knocking Live Video Broadcasting Cross Platform App for iPhone and Android Mobile Phones
http://androidforums.com/htc-evo-4g/144105-knocking-live.html