This is the app for absolutely exhaustive choice of iTunes tags to edit!
The developer is incredibly responsive, especially if you use their website or email. Great to see someone breaking out of the Atomic Parsley box!
It's stable and once the file is loaded, all the fields are reasonably clearly labelled as to what they are. For a first version, very good. What I would like to see is drag-and-drop file selection, and some documentation about what files it supports (I had no issue with standard iTunes files, but I'm curious about mp3's purchased elsewhere). Can't beat the price! Thanks for your generosity!