The app features a very minimal interface that is easy to hide, leaving a full screen blank canvas. Playing with the app briefly on the Surface Pro 3 and my desktop pc with a Monoprice 22' Smarttouch pen display, the experience is very nice. Pro membership also unlocks complete access to SketchBook on Windows desktop, Mac, Android, and iOS, including all upgrades as long as your membership is active.Pro membership: Other workflow improvements, including new ruler guides, flood fill, and much more.Pro membership: Full layer controls, including rich layer blending modes makes image manipulation easier than ever.Pro membership: Choose from a comprehensive brush library with pencils, pens, markers, and brushes, including new Synthetic and Smudge brushes.Sign in with a free SketchBook account and unlock the Layer Editor, Symmetry Tools, and more.Choose from over 10 preset brushes, including pencils, pens, and markers that deliver a natural drawing experience.Control the finest details of your art with up to a 2500% zoom.Open and Save layered PSD and TIFF files for easy interoperability with other applications, including SketchBook for desktop.The entire screen is your canvas with a full screen workspace and unobtrusive user interface.

Designed specifically for both pen and touch input on Windows tablets.Here's the product description from Windows Store:

Sketchbook free download for pc