LOL, if I were you, I'd just change "eReader" to "e-reader" and be done!
... in fact, since there are no "readers" that aren't "e" - apart from humans (and some trained dolphins or monkeys or...) - you could just say "readers", since I doubt that anyone would think you were looking for humans with touchscreen capabilities (in this present time, God knows what the future will bring!
).