So, has it helped you "tune" your ear? i.e., are you able to correct your pitch without the tool now that you've spent time practicing with it? I've often wondered about that. I learned guitar at such a young age, that I don't have a good recollection of the process of learning to have a reasonably good ear, or if it was something I already had and had to just learn to listen to.

As an adult, I've often gone years without seriously practicing music, and yet the basic ability to hear notes and tune instruments remains strong, no matter what. The ability to name notes and recognize chords on demand (so-called "relative pitch") does require me to refresh my memory with practice whenever I take a long break from music, but recognizing when things are sharp or flat, and by how much, seems to be permanent and require no practice no matter how long it's been. So, I theorize (and have read about science on the subject) that there may be a variety of parts of the mind that handle these subjects. But, I don't recall reading if they're all in-born skills or are acquired. Perfect pitch may be teachable to the very young...but not adults, so maybe my tuning ability simply developed and "stuck" because I was young. I dunno.