The Circle Theory App

Today's app is the Circle Theory app:

​Circle Theory (http://www.artsiness.com/Artsiness/Circle_Theory.html) Tool to assist seeing the relationship between notes; key signatures for major and minor scales; assists in transposing; guide to note intervals per musical mode; VGA adapter can be used to view the circle on an external screen or projector; tap or drag on the outer ring to change the tonic note and key signature; double-tap the outer ring to cycle through the inner ring displays; double-tap the center of the circle to cycle through the clefs; when the inner ring is displaying a musical mode, drag the inner ring to select a new mode; when the inner ring is displaying the transposition assistant, drag the inner ring to select a new starting note; (iOS 7.0 or later).