MPFreaker - Imagine a program that automatically fills in the missing information in your music library...
Automatic Tag Editor - Automatic Tag Editor Application for Android
Tune Sweeper - Show duplicates in your Music library. Automatically select which duplicates to keep and delete based on your preferences. Remove duplicates with one-click from your iTunes or Music app library.
MusicBrainz Picard - Official website for MusicBrainz Picard, a cross-platform music tagger written in Python.Downloads · MusicBrainz Blog · Picard 2.
TuneUp - TuneUp makes your music fresh and clean!
AMVidia Tag Editor for MAC - Discover the newest way of editing tags and renaming music files through the handy spreadsheet.