According to Variety, Ariana Grande it expected to headline Lollapalooza in August. Here's more:
"Multiple sources tell Variety that Grande has been booked for Lollapalooza, set to take place in Chicago’s Grant Park August 1-4, on top of her already announced slot at Coachella in April. The Lollapalooza lineup isn’t traditionally announced until the third week of March, so any official confirmation of Grande’s appearance as a headliner for one of the four evenings may be weeks or even months away."
Ariana will also be at the United Center in June for her Sweetener Tour! Are you excited?