Tenuto Music Theory
Rirpadev
音乐理论助手
johgru apps
Music Theory Companion
PG App Studio
MyMusicTheory - music theory
myrApps s.r.o.
Theory Test Pro
Well Informed Limited
音乐理论
Kirill Sidorov
Music Pro
Thien Bui
Sony Corporation
Touch Theory
DarkChibiShadow
Math theory
Sangakoo