Melinda Sheckells The iHeartRadio Music Festival, after 12 years as a staple event in Las Vegas’ datebook, took over the T-Mobile Arena Friday and Saturday with the top stars of music and podcasting, radio and streaming, canvassing both the audience, onstage and backstage. Known for its surprise collaborative performances and world premieres, the iHeartRadio Festival crosses genres and formats. This year belonged to country stars, legacy acts and viral sensations. Featuring performances from Black Eyed Peas, Lionel Richie, Morgan Wallen, Diplo, Pat Benatar and Neil Giraldo, Pitbull, Sam Smith and the Black Keys, the action behind the scenes began to roll around 6 p.m. on night one, all leading into a 7:30 p.m. showtime.