Justin Bieber's continuing allure for millions of young fans was cemented today when he hit the top of the iTunes album charts in nearly every country worldwide with "Believe Acoustic."

The album sees the 18-year-old strip down musically by doing acoustic versions of tracks from his 2012 album "Believe."

There's been a focus on one of three new tracks - the ballad 'Nothing Like Us.' As it's the only track on the album written solely by the young star and it's about a break-up, it's been widely reported to be about Bieber's split with fellow teen star Selena Gomez.

Not content with the popularity of his music, the Canadian heart-throb also became Twitter's most followed person earlier this month, overtaking Lady Gaga by over 100,000 followers.