Vinny's iPhone Vocoder

Vinny's shown off his iPhone vocoder in a couple videos and it looks hella fun. Does anybody know what app he's using or how to set that up?

Yeah I think it's called " I am T-Pain". Here 
http://iamtpain.smule.com/

Isn't it called 'I am T-Pain' or something like that?

I heard it's called "I am T-Pain" or something like that.

Thanks thanks that appears to be it.