Freehand design sketching on the iPad is for UX designers. Any app that lets you do freehand user interface sketches, either using finger tips or a capacitive stylus like the Pogo Sketch is what we're sharing here. If you drop non-iPad sketches, they will be booted.
Suggested tools to start: Autodesk Sketchbook Pro, Adobe Ideas, Penultimate, Brushes, OmniGraffle, Sundry Notes.
Sign my guestbook and share a random, weird or inspirational message or whatever is on your mind.