This series of apps is outstanding. Presented in a simple, concise manner, the exercises allow you to really hear and internalize the concepts being explained. Working the pattern through all keys is easy with the jam along, in addition to being able to change keys on the same page as the example. I've gotten so much out of just learning one pattern in the bebop b3/b5/b6 exercise that it's expanded my note choices and ideas in all my playing. Thanks so much for taking the mystery out of how to play outside the diatonic scale, yet still sound completely inside the chord-how to do that fluidly has plagued me for years, now it's all starting to come together and make sense.