Simple nonchromatic guitar tuner program for Mac, Windows, and TuningOnline. Plays notes in standard and nine alternative tunings includingOpen G, Open D, Open A, Open E, E Minor, Drop D, Double Drop D, HalfstepDown, and Celtic/DADGAD. There's also an individual note-player of threefull octaves, including all sharps. Originally developed exclusively forMac OS X. The supplemental Digital Pitch Pipes are a set of MP3/AAC/OggVorbis files for tuning on the go.