Audio Tuner 0.4

Audio Tuner enables you to tune just about any musical instrument by providing a spectrum analyzer and pitch-pipe.

If you have a microphone or audio in, simply play the instrument and Audio Tuner will analyze the pitch for you, telling you if the note is too high or too low. Audio Tuner also displays a real-time spectrum analysis for you.
Use the pitch pipe functionality if you wish to hear the correct note, enabling you to verify your tuning. Use the pitch pipe if you don't have a microphone. Supported instruments include: Guitar, Ukulele, Violin, Piano, Bass Guitar, Banjo, Mandolin, Autoharp and Cello.