How to do custom signal processing on iTunes/Apple Music

My app lets users apply special effects to songs. Currenty I use the MPMediaPickerController and AVAssetReader to select and copy songs from the user's itunes library into my sandbox. I have my own custom player that applies various effects.


This does not work well. Its very cumbesome for users to access their music

  1. They can only access songs that they have purchased from iTunes. There does not seem to be way to filter MPMediaPickerController so that it only shows songs they can access
  2. The song must have been down loaded to their device. It would be really nice if the MPMediaPickerController let users download songs as needed. Or better yet iOS had an api I could use to down load songs if needed.
  3. Users can not access streamed music. I.E. songs they did not purchase


Is there some other way to provide access?


Most of my users would love to purchase the songs they want to access from my app. Its easy of me to know that a user tried to access a song and ran into trouble. I wish there was a way to make easy for the to buy the song on the spot