How to make drawing app on PC, and Mobile.

1. Comparison events between PC and Mobile devices

Eventon PCon Mobile
click onclick, onmousedown ontouchstart
drag onmousemove ontouchmove
out onmouseup ontouchend

2. Live examples of both sides

On PC

On Mobile

There are only two differences.

First, event names ( as I noted on a table above ),
and "event.clientX" on PC is changed to "event.touches[0].clientY".

3. Resources

Exploring canvas drawing techniques (on Perfection Kills by kangax)

HTML5 for the Mobile Web: Touch Events