Kanye West has given his friend Jay-Z’s music streaming site Tidal a much-needed boost.
He has released his latest album The Life of Pablo exclusively for streaming on Tidal. Initially the album was also available for sale on West's own website but that link was then pulled.
Tidal's exclusive deal has seen its app leap to number one on the Apple App Store. It also reached the top 30 in the App Store's "Top Grossing" section.
That prompted West to tweet: "Man thank you so so so much everyone for signing up to Tidal. Tidal is now the number one app in the world!!!"
But for how long?
Tidal offers listeners a free listening period after signing up. The risk for Tidal is that once the album goes into wider release people will opt out of Tidal and listen elsewhere. Jay-Z is hoping that once people listen to what else is available they will opt to pay to stick around.
Tidal was bought last year by Jay-Z and sixteen other musicians from a Swedish company. It was re-launched with much fanfare but it has struggled.
Tidal offers "lossless" higher quality streams than its rivals. But its subscription rates are higher.
Jay-Z said last October that Tidal had one million paying subscribers.
Apple says it has eleven million paying subscribers. Spotify says it has around 20 million paying subscribers and another 75 million who listen for free (funded by ads in between the songs).
Tidal has also had to cope with technical glitches and management changes. Its other big problem has been that despite its high profile backers many listeners simply have not heard of it or have not been motivated enough to try it out.
That is something that Jay-Z's hoping to change by offering a series of exclusive releases.
Last month Rihanna released her latest album ANTI on Tidal and since then Beyoncé has delivered Formation.
Jay-Z did something similar last year. Prince, Nicki Minaj, Little Wayne and Calvin Harris are others who have released songs or videos exclusively on Tidal.
But Tidal is not the only site offering exclusives. Apple recently released an exclusive Taylor Swift concert on its streaming service.
Jay-Z knows that, which is why Tidal is also venturing into original TV shows like web series Money & Violence and comedy show No Small Talk.
Apple's big advantage over its rivals is that its streaming service is just part of a much larger business. But streaming sites like Tidal, Spotify, Pandora and SoundCloud need to survive on their own merits.
There is talk that Spotify is looking for hundreds of millions of dollars in additional investment.
Rumours abound that Jay-Z would like to sell Tidal.
So he will be thrilled with the helping hand he's been given by his pal Kanye West.
Of course friendship goes both ways.
West tweeted that "Tidal is also funding a lot of my scripted content ideas. It's a new day people. More Ultra Light Dreams to be realised".
That is just as well for Kanye who also tweeted that he is US$53 million in debt and would like to talk to tech billionaire Mark Zuckerberg about giving him one billion dollars to fund his future projects.