There is no competition!
One of the main reasons that I held off purchasing an iPad was because SingSnap wasnt available on it.
Its an amazing app under windows and the developers have done a terrific job on the iPad.
20,000+ songs. Put on some headphones and hear the music and your voice. No synching of voice and music required on the iPad as under windows. The recording is great and most of the windows based features are there as well.
SingSnap is the next best thing after World Peace! :)
JRSS59 about
SingSnap Karaoke, v1.0.2