iHeartRadio's ALTer EGO fest at L.A.'s always-Fabulous Forum featured performances by Billie Eilish, The Black Keys, Blink-182, Coldplay, The Lumineers, SHAED and Rex Orange County. In this memorable shot, RCA artist Rex feels that warm radio embrace shortly before iHeart's Lisa Worden quizzed him about hotspots in Tustin, Placentia and Yorba Linda. Seen wondering what rhymes with "Orange" are (l-r) RCA's Artie Gentile, iHeart's Brad Hardin, Rex, Lisa and RCA's Dennis Blair. Some performance highlights appear below.

Interscope's Eilish catches air while brother FINNEAS holds it down.

Warner Records' Black Keys introduce the kids to an exciting new form called "blues."

Columbia's Blink-182 significantly expanded the event's color palette.

Dualtone's Lumineers kick up a folkin' racket.

Photo credits: Getty Images, Wes and Alex, Ashley Osborn