A good device, well set up, makes the whole thing much more pleasant. Notice that I have tried to match the brightness of the screen to mimic the page under natural light; that helps minimise eye strain.
You also need to learn new strategies for navigating the books. Get a good app which allows you to add your own bookmarks. The ability to pull out to a thumbnail view of multiple pages is also great. And, of course, the search function can make niche rules easier to look up.
Just curious: what app are you using for this purpose?