Originally Posted by DrNefario
On the Kobo, you can only do one direction that way, and which direction it is depends on which hand you're holding the device with. Otherwise you need to reach half way across the screen or swipe. Okay, normally you want to go forwards, but it's still kind of annoying.
That would also be true with buttons, though. If you had your thumb on the "Page Forward" button, you'd have to move it to do a "Page Back".
I can only imagine the agonies those people who worry about moving their thumb a fraction of an inch must have gone through when turning the page of a paper book