What is pentatonic? What is mode? If you think so, just install this app. * * * * * This app show you many scales that need every time you play the guitar solo. * * * * * You can select minor pentatonic, blue note, major pentatonic, chord tone, and mode by touching ON/OFF button on the screen. * * * * * You can see that same time to compare with others. Appearance is designed to know and learn how many intervals are there from root. * * * * * Of course, you can change the root and other options any time particularly, by using hardware option key.