Super-Awesome!!! Helped me do just what I needed to do! That is- to set MP3 tags from filenames, and fix a few files names as well. Big thanks to the hard work of the author. Can hardly believe it is free.
A HUGE THANK YOU to the author. Now Downcast for iOS can tell these songs apart - after they were recorded off radio as 1 big file, then split using Rogue Amoeba Fission. (Which is so good & fast at this, it is amazing it didn't get a speeding ticket!). But Fission sadly made all the MP3 tags the same, which confused Downcast greatly. This Kid3 app fixed all that quickly.
I do recommend spending like 5 minutes with the built in help manual so you get up to speed quickly. Totally worth it. This is a very easy & very fast app.... IF you read even a little bit of the manual.