Headline acts for this year's iTunes Festival are to include Justin Timberlake, Jessie J and Queens of the Stone Age.
The free series of events will include more than 60 acts to be performed throughout September at London's Roundhouse.
Also on the bill, as the first batch of names was released today, are Primal Scream, Thirty Seconds To Mars and Jake Bugg.
Jessie J axed a tour earlier this year because she did not want to play the sell-out shows before the release of her album, which had been delayed.
She said: "I'll be back with new music, a new look and a party you're all invited to."
Also on the bill are Phoenix and Jack Johnson, with others to be announced over the coming weeks.
Apple executive Eddy Cue said: "This year's iTunes Festival is the best ever with an incredible lineup of global superstars and stellar emerging artists. We're honoured so many renowned artists are part of this year's lineup."
Fans can apply for tickets at itunes.com/festival and the performances are also being streamed online.
R'nB star Usher headlined the first night of the iTunes Festival at Camden's Roundhouse in London. The festival takes place all through September.
Chart-topping stars JLS are the latest addition to this year's iTunes Festival.
The quartet, who were among the acts performing at the Diamond Jubilee concert at Buckingham Palace this week, will make their debut at the annual free festival.
They join acts as diverse as Jack White and One Direction on the bill for the month-long event.
JLS - whose hits include Everybody In Love and She Makes Me Wanna - will play the Roundhouse in Camden, north London, on September 6.
The shows will be broadcast online and fans can apply for free tickets at www.itunesfestival.com.