My only complaint about this app is that it's handicapped by the sluggish response of the stock S Pen vector output.

After trying Autodesk Sketchbook, I now realize how fast an Android app can respond to pen input, and I find it disappointing when I use anything else.

Your app has a perfectly simple and intuitive interface, if it could somehow attain the lightning fast response of Sketchbook, in my mind it would be perfect.