Demi Lovato

Demi Lovato broke out as a Disney Channel star in Camp Rock before becoming one of pop's most powerful vocalists. Hits like "Sorry Not Sorry," "Heart Attack," and "Cool for the Summer" made her a fixture on the charts, and she has since expanded into acting, producing, and documentary filmmaking. Her rock-leaning later albums showed off a grittier, harder-edged side of her voice.