[BeetleB]

Resolution is fairly low. You can get cheaper Kobo's with higher resolution. Here's a 7" one:

https://us.kobobooks.com/collections/ereaders/products/certi...

Kobos are fairly hackable, and I suspect one could program a Kobo to do the same as what he is doing.

[sitkack]

Exactly, the market he is trying to serve has the customer as his own competitor. That is a bad position to be in. I wouldn't want to be my own customer, would you?

Two recommendations.

1) Go wireless with enough power for like 500 screen updates for 6 weeks between recharges.

2) Find a market where your customers can't make the product