Ariana Grande wore cat ears, Taylor Swift was pretty in pink at iHeartRadio Festival

The 2014 iHeartRadio music festival in Las Vegas brought out some of the biggest names in pop music, and with them came some wild fashions and performances.

Taylor Swift rocked a pretty-in-pink two-piece outfit for her performance, though the artist didn't reveal any other new details or songs from her forthcoming new album “1989.”

Ariana Grande might be celebrating Halloween a little early, as she donned little black cat ears with her all-black getup at the MGM Grand Garden Arena event in Las Vegas. She and Nicki Minaj took the stage together to perform certifiable hit “Bang Bang.”

Iggy Azalea looked a little go-go, Coldplay was casual, 5 Seconds Of Summer and One Direction smiled through the (fan) screaming… check out more photos from the weekend event below.