Bsharp

Absolute pitch is something children can still pick up, and the window closes around age six. Bsharp is an Android app aimed at that window, following Eguchi's chord identification method: the child hears a piano chord and taps the flag whose color stands for it. Training opens with red and yellow, and a new color arrives only after every chord already in play is named with full accuracy.

Sessions are deliberately short, roughly five a day at two or three minutes each, about twenty to twenty-five identifications. The app logs accuracy, weights harder chords so they come up more often, and keeps a separate profile for each child. Nine white-key chords come first, then five black-key ones. The code is open source, derived from Paul Ganssle's CIM Trainer, with the repository on GitHub and a build on the Play Store.