- Check "Show chords on piano?"

- Check "Play chord sounds"

- Uncheck "Play feedback sounds"

For the "Chords", start with just Red and Blue. Then add Yellow.

I don't have perfect pitch, and I could not distinguish between Red and Blue, when Yellow was in the mix and the feedback sounds interrupted the trials.

Black and Green were much easier for me to differentiate, but Red / Blue is really difficult.

It makes a noise and then has buttons labelled red, blue, and yellow. How am I supposed to know what colour that sound was? Do sounds naturally have associated colours? Is this even the question I'm being asked? It doesn't say what to do or how I am meant to choose the colour.

EDIT: From some trial and error, I still don't get it. It seemed to me that blue was the low tone and red was the high tone but then I got a tone that was definitely lower than a previous yellow tone and it was supposedly blue. Potentially a bug?

My brief story: I was using that as a PWA, but encountered some snags when using it on mobile.

I cloned it and fixed those, which required switching to Android WebView instead of a PWA. I opened a PR but Paul said he preferred that I make my own fork with a new name. At that point I decided to do a full rewrite instead of just a fork (from Jekyll to TypeScript), and that's the version I posted here.

Edit: you can also clone and build the apk if you'd like, there are instructions at the bottom of the README