Autodesk has launched a iPhone app called "Sketchbook mobile" They call it a professional grade drawing and paint application for the iPhone and iPod touch that uses the same paint engine as used in Autodesk's Sketchbook software What's interesting about it-for 3GS users, you can have up to 6 layers instead of 3 for other devices and a increased canvas size (1024 x 662 compared to 600 x 400). First impression of it is that the UI looks to be very neatly designed-I like the selection of brush styles on offer in particular. Autodesk Sketchbook Mobile
update out What's new - Patented gesture-based marking menus - E-mail PSD format (preserving layers) - Layer opacity, Layer delete - Double tap exit from Brush & Layer editors - Import Landscape-oriented images - Brush preview on resize - Stippling - Bug fixes love this app