Asketch

Asketch is a unique and versatile sketch pad. It allows creativity on the go, anytime, anywhere.
Its deliberate simplicity makes it perfect for beginners who want to learn to draw;
equally, advanced artists will find a wonderful buttery, tonal canvas for their life studies, cartoons, abstracts, landscapes and other subjects. The app is engineered to deliver rapid, but powerful image capture, facilitated by a great transform function that allows you to pick up the drawing, resize it and move it around the canvas, and a amazing zoom that lets you draw in minute detail. So if you want to put a traditional, but digital sketch pad in your pocket, this is the app for you.
Features and functionality:
Gesture based drawing interface: Changing the surface area of your finger on the screen controls the focus of the drawing. Supports pressure sensitive drawing on iPhones that support pressure sensitivity.
Image zooming that actually works: Do amazing detail work when zoomed in. No pixelation of brushes while drawing.
Image transformation: Scale/Rotate the image via a simple pinch gesture.
50 Levels of undo/redo. Swipe the undo/redo button to toggle back and forth. Hold down the button for rapid unwind/rewind.