Cool/weird iPhone app of the day: Stanton Studio has released ToneTune, a “multiple tuning fork” that helps tune stringed instruments to the correct pitch by ear, “without searching through hard-to-find books or the web.”

The application is loaded with standard and alternate tunings, over 60 in all, for guitars and other instruments. Users select a tuning, and tap the “string” on the touch-screen for the correct pitch. ToneTune can also play the tunings as consecutive strings (E-A-D-G-B-E for standard guitar tuning, for example), or as single pitches. Individual pitches can also be played over a ten-octave range.

Other features of this application include:

• Order of instrument tunings list can be changed to user’s liking
• The tunings are based on equal temperament
• 128 individually-playable notes from C1 (MIDI 0) up to G9 (MIDI 127)
• Notes read in ASA or Helmholtz
• A4 base frequency adjustable between 430 hz and 450 hz
• Users can vary the note play length, and the pause before the note play.

A full list of instrument tunings is at this link, and includes the bouzouki, the banjo, and the 4-stringed biwa (and that is just among the “B” listings). Retailing for $2.99 in the iTunes app store, it’s a lot less expensive than a separate electronic tuner, and would be nice for carrying around tuning information in your pocket.