Sketch Book Mobile Express App is a commendable effort by Autodesk team, By using pressure-sensitive features of tablets and smartphones, Sketch Book gives you a boosting experience and platform to create professional artistic sketches and creative effects.
Sketch Book features all the necessary tools for professional grade sketching using the same engine of Autodesk Sketch Book Pro software. Sketch Book Mobile App has all the tools like artistic brushes, layer support, customizable colour swatches and much more. You can also sketch any picture by placing it in background as shown in the video below :
It’s a free version, paid version has more features.