Apple says 33 million iTunes account holders have accessed U2's free album.
Company senior vice president Eddy Cue gave the first usage numbers for the surprise Songs Of Freedom release by the company.
Apple gave the album to 500 million iTunes account holders last week during its iPhone 6 unveiling news conference.
Mr Cue called the number record-breaking, but did not elaborate. The figure includes customers who downloaded the album from their iCloud account, streamed it or used iTunes' radio player to hear it.
Apple paid the Irish rock band for a five-week exclusive window during which the album is only available to its customers. Songs Of Innocence will be released on October 14 to the general public.