This looks pretty cool. I really like the idea of having different graph papers, esp. the isometric ones. I've tried several iPad notebook apps. They all seem ok. I think it's just me but I have difficulty writing clearly on an iPad even with a stylus (my handwriting is crap). Nice work on this.
I'll echo this sentiment. Been listening to a lot of music from Mali and being really productive with it on. Highly recommend Khaira Arby, Ali Farka Touré and Amadou & Mariam.
This looks like a pretty cool project. I would love to try it out once your servers cool down, particularly your API. I'm playing around with APIs for Harvest and Freshbooks now. Full disclosure: I created a minimalist time tracking tool for freelancers/agency folks that lowers the barrier to logging your work:
Yes we have an API on our roadmap but no exact date of release yet I'm afraid. Still fixing some fundamentals :-) I'm keen to keep abreast of your tool too.