Katy Perry calls beau John Mayer 'incredible, inspiring boyfriend'

Katy Perry gushed about her boyfriend John Mayer on Twitter, to urge fans to buy his latest album 'Paradise Valley'.

The popstar wrote in her tweet that something very special was happening on iTunes, as her "incredible, inspiring boyfriend" Mayer was releasing his latest album, Us Magazine reported.

The on-off couple, who have always kept their affair secret, have been more open about their relationship, following the release of their first-ever debut duet, 'Who You Love'.