U2 singer Bono has said sorry for striking a deal with Apple that would see the band’s latest album automatically appear in the libraries of iTunes users.

The album ‘Songs of Innocence’ appeared in the libraries of an estimated 500 million iTunes users, in a publicity stunt for the launch of the latest iPhone, prompting a fierce backlash against the band.

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In a video interview on Facebook, Bono was asked: “Can you please never release an album on iTunes that automatically downloads to people’s playlists ever again? It’s really rude.”

“Oops, I’m really sorry about that,” the singer replied.

The 54-year-old singer took responsibility for the idea.

“I had this beautiful idea and we kind of got carried away with ourselves,” Bono said.

“Artists are prone to that kind of thing. Drop of megalomania, touch of generosity, dash of self-promotion and deep fear that these songs that we poured our life into over the last few years mightn’t be heard.

“There’s a lot of noise out there.

“I guess we got a little noisy ourselves to get through it.”

Despite getting fans off side, the September 9 free release was expected to pay off handsomely for the already-wealthy rockers, with several reports saying that Apple had committed $US100 million ($A108.20 million) to distribute the album as part of its promotion campaign for the iPhone 6.

But few predicted that U2 has created a new model, with lesser-known bands unlikely to survive by giving away their music.

So many people found it presumptuous that the entire world would want U2′s album that Apple offered special advice on its website on how to delete it.

“I don’t think it was very good marketing. I think that’s been proven out by the commentary and the backlash. It was very heavy-handed and inappropriate,” said Eric Levin, owner of the independent store Criminal Records in Atlanta.

Bono, known in recent years for his campaign against global poverty, said that U2 started with an in-your-face punk spirit and that the album release was part of that.

“You want to be part of the zeitgeist, sometimes you have to smash and grab,” said Bono, who dedicated the first song on the album to late punk icon Joey Ramone.

U2 is not the first band to experiment with free releases amid the rapid changes in the music industry.

Radiohead in 2007 let fans pay whatever they wanted for album In Rainbows. But the move by the acclaimed experimental rockers, who eschew corporate sponsorship, triggered more curiosity than criticism.