Corel kicked off a new version of their desktop art app, Painter 2015, and along with it they've included an Android companion app. The main focus is on a wide range of brush types, though Painter Mobile also has layer support, symmetry tools, and all of the usual functions you'd expect.
Creations can be exported directly into the desktop app, or in standard formats like JPG and PNG. 16 brushes are included in the free version, or you can get the full 70 with a $4.99 upgrade.
Adobe already has Photoshop Touch offering a whole lot of similar cross-platform functionality, but for those that are digital artists rather than photographers, Corel's offering may be a little more attractive. How many of you guys work with digital art? Is it viable to use your Android device to do preliminary sketches? What kind of stylus do you use?