Pandora buys Rdio technology to offer better on-demand music streaming services similar to Apple Music and Spotify as Ad Age explains in its latest Dec 23 article.

Ad Age also features Elf as a premium partner that can help clients with changes in the radio and streaming audio market.
 

http://adage.com/lookbook/article/radio-and-streaming-audio/pandora-buys-rdio-technology-shifts-business-plan/301564/