Very limited capabilities
I just paid for this thing 5 minutes ago, and do I have buyer’s remorse! This thing doesn’t do 1/10 of what the ancient Media Rage does. Media Rage isn’t even supposed to mess with m4as of any kind, yet will find and attach artwork, and allow one to modify such files far beyond what this thing does. What Media Rage won’t do is modify sorting tags even though they are listed. Again, that app is essentially for mp3s yet does more that Meta. Foolishly thinking that what Media Rage does would be the norm and that Meta sepcifically listing m4as as one of its reasons for existing would make it my all in one tag editor, I was shocked at how little this thing does. Even if I could just edit the sorting tags, I would feel better, but those tags aren’t even available. Instead, I just threw away $15 on an app that does only a tenth that Media Rage has been doing for my Apple Lossless and ACC files for years.
I hate to discourage an Apple developer, but get yourself a copy of Media Rage and see what it does. Then make Meta do all that Media Rage can do for mp3s for m4as of all kinds. As it is, I’m going back to Media Rage, because it can do more for and to Apple Lossless and ACC files that Meta can even though it’s not designed to work with those files.
Joe Blowinski about Meta — Music Tag Editor