After reading up on this subject Apple have only spent a small fraction of their cash reserve on what could be the most important purchase the company has made so far. Dr Dre owns 25% of Beats Electronics but I think Jimmy Iovine, cofounder of Beats Electronics and his network are the key the this deal. Watch out Spotify and Deezer, iTunes is about to change!
http://www.dailydot.com/technology/apple-beats-jimmy-iovine-dr-dre/