"Apps should not ... include the ability to save, convert, or download media from third-party sources (e.g. Apple Music, YouTube, SoundCloud, Vimeo, etc.) without explicit authorization from those sources." Maybe I need to get explicit authorization from dropbox?

These are all my original recordings. I made them mostly at my house. Some of them I made in a recording studio but I paid for their production myself, without a record company. I'm not under contract with any record company. I'm not sure how I can prove that I own the rights.