This app is an app to help you memorize the note names on the frets (fingerboards) of stringed instruments such as guitars. Supported instruments are guitar, bass and ukulele. (If you have an instrument that you would like to support, please contact support Please. ) It is an ideal app for those who want to grasp the note name of the fingerboard by learning music theory or improvisation! How to use First, let's roughly learn each fret vertically at the beginner level. (It is effective to refer to the fifth circle of hints) Once you have learned it to some extent, let's learn it randomly at the advanced level. Let's do it until we can directly answer which string and which fret is XX!