Tracy Morgan hosts the 2013 Billboard Music Awards at the MGM Grand Garden Arena. (Photo by Ethan Miller/Getty Images)

Taylor Swift performs the evening's most elaborately staged set. (Photo by Ethan Miller/Getty Images)

Psy speaks during the 2013 Billboard Music Awards. (Photo by Ethan Miller/Getty Images)

Bruno Mars performs. (Photo by Ethan Miller/Getty Images)

Jennifer Lopez performs onstage during the show. (Photo by Ethan Miller/Getty Images)

Shania Twain presents the award for “Top Rap Artist” to Nicki Minaj . (Photo by Ethan Miller/Getty Images)

Will.i.am presents the award for top touring artist to Madonna. (Photo by Chris Pizzello/Invision)

Justin Bieber performs during the show. (Photo by Chris Pizzello/Invision)

Caroline Hjelt, of musical group Icona Pop, performs at the Billboard Music Awards. (Photo by Chris Pizzello/Invision)

Selena Gomez performs during the 2013 Billboard Music Awards. (Photo by Ethan Miller/Getty Images)

Taylor Swift performs at the Billboard Music Awards. (Photo by Chris Pizzello/Invision)

Nicki Minaj perfroms during the show. (Photo by Ethan Miller/Getty Images)

Nicki Minaj and Lil Wayne perform during the 2013 Billboard Music Awards. (Photo by Ethan Miller/Getty Images)

Christina Aguilera and Pitbull performs during the show. (Photo by Chris Pizzello/Invision)

Gabriel Mann and Stana Katic speak during the show. (Photo by Chris Pizzello/Invision)

Taylor Swift accepts the award for top Billboard 200 album for “Red”. (Photo by Chris Pizzello/Invision)

Miley Cyrus presents the award for top male artist to Justin Bieber. (Photo by Chris Pizzello/Invision)

Prince, who received the icon award, closes the show with a melody of his jams. (Photo by Ethan Miller/Getty Images)