Len Blavatnik, the billionaire owner of Warner Music Group, has led a £40 million investment in the music streaming company started by rapper Dr Dre and American Idol judge Jimmy Iovine. Dr Dre's company Beats, which is known for making headphones, will spend the money on a new venture, an internet music service called Daisy. Like rival Spotify – which is valued at $3bn but has yet to make a profit – Daisy will let listeners select their own playlists.