Watch: Childish Gambino Talks Ariana Grande Collab, New Mixtape at iHeartRadio Fest

Childish Gambino at iHeartRadio 2014
Christopher Polk/Getty Images for Clear Channel

Donald Glover (aka Childish Gambino) performs onstage during the 2014 iHeartRadio Music Festival at the MGM Grand Garden Arena on September 19, 2014 in Las Vegas, Nevada. 

Childish Gambino surprised fans at the 2014 iHeartRadio Music Festival by joining Ariana Grande on stage to deliver a cheeky guest rap on "Break Your Heart Right Back," from Grande’s new chart-topping album My Everything.

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Gambino says Grande was very encouraging during the recording process. “She came in when I was recording and was like, ‘That’s great. I love the tone of your voice,’” he recalls. “She knows her stuff about music and rap.”

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The rapper also divulged some details about his forthcoming STN MTN / KAUAI mixtape, due later this year on DJ Drama’s Gangsta Grillz label.

“I feel like it’s the first concept mixtape ever,” Gambino says. “It’s a mixtape that goes into the EP but they’re connected. It’s the same character and the same story from Because the Internet and Camp. It’s kind of like a nice in between for the next album.”

Gambino will perform on Saturday at the iHeartRadio Music Festival Village in the lot across from Luxor Hotel & Casino.