Plays tuning notes for lots of instruments.
Guitar, 6 and 12 strings, Tres, Bass, 4 - 6 strings.
Ukulele, Mandolin family, Bouzouki, Nyckelharpa.
Banjo 4 - 5 strings, Balalaika family, Violin, Viola and Cello.
Turn up the volume on your iPhone and tune your instrument.
The app also works for the iPad,
but is specially designed for iPhone 4 and 5.