I know the folks at Autodesk get asked this a lot on the Sketchbook social media pages, but I don't think I'm alone in saying many of us would LOVE to see the option to create and/or import custom brushes to the mobile versions of the app. I love Sketchbook's brush engine, so this would be the perfect icing on the cake - especially since Apple included Pencil support with the new 6th gen iPad.