Katy Perry (and her purple hair) made an appearance on American Idol tonight.

https://twitter.com/#!/BriannaInfinity/status/195674350320488448

https://twitter.com/#!/BluFlowerGirl/status/195677380168253440

https://twitter.com/#!/EpicShizGaming/status/195677361646223360

https://twitter.com/#!/wildcatgirl13/status/195676845738442752

https://twitter.com/#!/kegiles/status/195675317631852545

https://twitter.com/#!/justaddcream/status/195675249768022016