Probably the most widely known digital painting app is SketchBook Pro.This app is available on android and ios. There is also SketchBook Pro 6 for Desktop PCs (I have that too). It has 165 brushes, probably half of them are stickers and the other half are regular brushes such as pencil, pen, paintbrushes, texture brushes, and airbrush.It does have a smudge brush, but no blending brushes. It has several tools including symmetry tools, guides, transform tools, line drawing styles, fill tool, and text. You can adjust the brushes, use layers, and select Copic colors. It has a nice UI that vanishes when you tap on the circle at the bottom of the screen.You can have paintings up to 2560 x 2560 pixels. I really like the smoothness of this app and there is no lag on my Note Tablets. I would like to see blending brushes like the PC program SketchBook Pro 6 has in it. Hopefully that will be added in future updates.
SketchBook Pro Interface
Made in SketchBook Pro. Prints of this painting are available http://instaprints.com/profiles/1-ellie-taylor.html and http://fineartamerica.com/profiles/1-ellie-taylor.html