Nothing profound...just doodling with "Paper," one of my favorite iPad drawing apps. I'm not fond of the fact that there's no "resistance" between me and the glass. Does that make sense? What I'm trying to say is that paper, canvas, and other grounds offer enough traction so that my hand doesn't go sliding out of control. I also dislike the fact that I can't use it outdoors on a bright day. (So much for plein-air experimentation.) What I do like about drawing/painting on the iPad is that it's great for experiments, especially since there's neither wasted paint nor the need to clean anything. As for drawing on glass...practice, practice, practice!