Arriving in style before preparing to take the stage, Demi Lovato and Avril Lavigne attended 102.7 KIIS FM's Wango Tango at The Home Depot Center in Carson, California on Saturday (May 11).

The "Heart Attack" singer donned an all black semi-sheer outfit with matching nail polish and jewelery, while the "Sk8er Boi" songstress opted for a black sparkling vest, black top, shiny navy pants, and platform heels as she smiled on the red carpet.

Hosted by Ryan Seacrest with a special guest host appearance by Britney Spears, the annual day-long concert also features performances by will.i.am, Bruno Mars, Maroon 5, Flo Rida, Miguel, and Fall Out Boy.

Sharing photos of herself backstage, with Bruno Mars, and performing in front of the crowd, Avril tweeted, "Epic day! #WangoTango2013."