Check out Amy Hoy’s JavaScript Boot Camp tutorial, highly recommended!
None
Free bonus: get a $5 off coupon code for my Retinafy ebook when you subscribe!
The aerogel-weight mobile JavaScript framework, which also works great for Safari and Chrome extensions. The jQuery-compatible API makes it easy to pick up, and it's just 5k to 7k in size!
Why not try Noko, the best time tracking software ever! :)