Guitar Tuner is a tool for tuning classical and acoustic guitars. Some of the features are
* It can listen to instrument sound and measure the sound frequency.
* It can also produce reference sounds when touching the strings on screen.
* you can tune easily by following directions like tighten-loosen
* you can tune by both selecting a string or in auto-selection mode
* there are also "string may be broken" warnings (in manual mode)
* supports more than 50 tuning styles
* callibration between 424-456Hz
* metronome with beat groupings, vibration, torch, etc