The few other online trackers that I found where pretty simple (but I probably missed some), I hope I will be able to expand this one a little further. Not so much with effects but more with different types of instruments.
I didn't directly base this on anything and I am more of a programmer than a musician. But I have used protracker and modplug.
Btw, I am waiting for Audio Workers support in browsers so it will be really possible to generate audio in the browser without stutters. Although I am pretty happy with how well this actually seems to work right now.
I announce all updates on new features etc. on twitter https://twitter.com/mustrackonline
. This is a hobby project so no promises when anything will be done but I hope to finish the basic effects within a few weeks (set volume, volume slide, set pitch, pitch slide, panning).