Tidal

CNNMoney obtained a copy of the petition which was filed Friday. It outlines an agreement between Tidal -- owned by the rapper Jay Z -- and Prince made before the pop star's death in April from an accidental overdose of the opioid fentanyl.

According to the document, Prince granted Tidal worldwide digital streaming rights to his next two "newly recorded and previously unreleased full length studio albums" in 2015.

The singer was well known for protecting his music, pulling it from You Tube and declining streaming services requests.

When it was released in November, it could only be bought physically or downloaded.

The album, which will be available to members on Friday, includes the songs Hello and When We Were Young.

In June, Apple reached an agreement with two leading indie music groups, paving the way for thousands of labels to join its new streaming service.

The music streaming service is giving away a free Chromecast to first-time subscribers who take out a three-month subscription.

The deal is valid in the UK and US until February 28, but anyone who has held a premium account in the past does not qualify for the freebie.

Spotify has launched the promotion at a time when TIDAL is shooting up the App Store charts thanks to its exclusivity deal on Kanye West's Life of Pablo.

Meanwhile, Apple Music has emerged as a credible threat to Spotify's dominance, having reached 11 million paying customers in its first year.