I'm working on a music sequencer app for Web and mobile devices. I have finally managed to make fully working drum sequencer than can store 5 different patterns and play them in sequence. Right now only there are only 7 different drum kits, but i'm planning to add custom kits (user can use his/her samples). After this i'm planning to add some kind of Roland TB-303 emulation (bass synth). Only thing not working right now is SOLO button.
Features:
7 different drum kits
Load and save drum pattern
Play up to 5 patterns
Set BPM
TO DO:
Bass synth (TB-303) or something similar
Mixer with effects
Make sequencer in different measures (1/4,1/8,1/16)
Saving and loading whole project
Preview here (use Chrome for best results): http://www.djape.tk/games/sequencer/