A couple of the e-Ink readers I own have stylus input but... they suck, quite frankly. You need a high sensitivity digitizing grid and a lot of processing power to run it in order to capture input like that in close enough to real time that it doesn't look like an Etch-a-Sketch. I own a Tegra Note 7 which when new a year and a half ago was one of the most powerful 7" tablets around, and it has a capacitive stylus and a processor core dedicated to stylus input. It's okay for taking notes but it fails when it comes to dashing off autographs.