i-Diatnonic is simple utility application to know the Diatonic code of specified key.
・When you'ld like to change the key of score.
・When you don't know what code to play in the key.
・When your band's vocalist wish you to down the key.
You can change a key, and up / down half tone easily.
And of course, You can see the minor key's diatonic and 7th key's diatonic too.