Any way to improve the sensitivity or smoothness or slipperiness of the screen? (Or maybe there's a way to make my fingers smoother?) When I play Fruit Ninja or Paper Ninja, sometimes my fingers glide nice and easy over the screen, and I do really well, but after a while they begin to have some resistance, and the strokes don't register as well. Then I lose. The first thing I thought of was Rain-X, a product for making a car windshield smoother, so rain beads up. But I couldn't find much discussion of this kind of thing on the net. Any ideas, tips, tricks?