The iHeartRadio Music Festival kicked off in Las Vegas last night. Ryan Seacrest emceed the event and was joined on stage at the top of the show by Britney Spears. The crowd went wild for Britney had colorful pink and blue highlights in her hair and wore a tight black minidress. No Doubt was the first act to belt out their hits, with a mix of current singles like "Settle Down" and onetime chart toppers "Don't Speak," "It's My Life," and "Hella Good." The audience got a special surprise when Pink joined Gwen Stefani on stage for "Just a Girl."
Miley Cyrus made the trip to Sin City as a presenter and teamed up with Olympic gold medalist Ryan Lochte to introduce Lil Wayne to the sold-out crowd. The night was a celebration of music genres with country, rap, R&B, pop, electronic, and rock artists coming together to perform. Country stars Jason Aldean and Miranda Lambert, who also performed with her side project the Pistol Annies, had the crowd on their feet, as did Usher, who teamed up for a duet with Swedish House Mafia, and Internet sensation Psy got lots attention for his hot dance moves. Rihanna closed down the four-hour block of live acts with a high-energy performance that included "Don't Stop the Music" and her latest release "Cockiness (Love It)." The fun continues again later today with Enrique Iglesias, Calvin Harris, Pink, and Taylor Swift expected to entertain the crowds.