From hit soundtracks to 'Sesame Street' to in-progress albums by superstars, this young talent is turning up everywhere.
"I Love It," the Icona Pop song co-written by Charli, played during a coke binge by Hannah Horvath, Lena Dunham's character on the show.
The singer, who claims 13 No. 1s on the Billboard Hot 100, has brought in Charli to work with her.
THE FAULT IN OUR STARS
This box-office hit's soundtrack includes "Boom Clap" as the lead single. Charli saw the movie but never finished the book.