I'm interested in the persistentID property of MPMediaItem.
Assuming I obtained the MPMediaItem using MPMediaQuery songsQuery, and assuming that the song which was returned is a song that the user purchased from the iTunes Store or Apple Music, will this value uniquely identify the song across all Apple devices or is it specific to that user or that device?
In other words, if two people buy the same song from the same album and add it to their music library, and my app queries for that song, will it read the same persistentID for both users?
If that's not the case, is there another way I can get a unique ID number for the song?
Finally, is there a way I can distinguish songs that were obtained from Apple versus songs that were added to the user's library by ripping a disc or adding an MP3 file, etc?