Have you heard of the OpenDyslexic font? I'm always surprised how many people haven't. I've known a couple people that it helped quite a lot. Of course, it won't help if you're reading print books
I'll have to look into some of these responses. Up till now I've just used gimp because it's already installed. I always think I should find something faster just for viewing but I never do
or, hear me out, a backlit piece of paper