Jay Z has sold millions of records, helped launch the careers of stars including Rihanna and Kanye West, and now the music mogul is competing against music streaming giant Spotify with his own music platform.

With the help of famous friends, the 45-year-old rapper and businessman has relaunched Tidal, his recently purchased online streaming service.

Artists such as his wife Beyonce, Madonna, Coldplay, Alicia keys and Rihanna, were amongst the stars that transformed their Twitter avatars into turquoise squares in support of his new venture, which goes live at 10pm GMT on 30 March 2015.

However, Chris Brown, who has a notoriously strained relationship with the label boss refused to lend his support by changing his icon. After Jay-Z's recent, negative comments surrounding Chris Brown, it comes as no surprise that the pair may not be seeing eye-to-eye at the moment.

The producer allegedly stated he thought the drama surrounding Chris Brown's latest scandal involving his ex Karrueche Tran was "karma finally catching up with the young star", a source revealed to Hollywood Life.

Although Taylor Swift also didn't change her Twitter avatar, she showed her support by giving Tidal access to her entire discography.

Tidal sound

The streaming site will be available through computers and smartphones operating on both a general website and application-type platforms.

Unlike Spotify, whose users can listen for free to a 160kbps stream (opting to subscribe for an ad-free, higher quality 320kbps experience), Tidal will only be available through subscription options.

The entry-level 'Tidal Premium' tier offers standard quality audio (320kbps or 96kbps - presumably catering to desktop and mobile usage scenarios) from $9.99 / £9.99 per month. The 'Tidal Hi-Fi' tier adds lossless FLAC audio (1411kbps) for $19.99 / £19.99 per month. Both subscription levels offer high quality music videos and curated editorial content.

The service will be available in 19 different countries including the US and the UK, but will be accessible to many more including Slovenia, Malta and Denmark later in 2015.

In February, Jayz Z acquired the company for $56m (£38m) from Aspiro, a Scandinavian media technology company. Although the interface previously launched in October 2014, it is thought that Jay Z plans to uses his reputation to make it globally-recognised brand.