This is a tuner for open-code tuning of a guitar.
You choose an open-code on a memu, and push a tuning fork button.
The head of a guitar appears and six sound is displayed.
The head of a guitar has two kinds and you can change it.
Letter names are buttons.
If a button is pushed, sound will sound for 12 seconds.
What's new (v1.6)
This update from Apple will improve the functionality of this app. No new features are included.
The method which was playing a sound file was abolished, and the reference tone was changed so that I might rumble by a square wave.