[SmokeAndMirrors]

Well, I suppose it would really depend on what the problem is. In older people, the amount of light their eyes can actually take in declines. At 70, you only take in about 20% of the light. So two people, one who's 20 and one who's 70, might have vision problems, but their problems are likely to be very different because of the general affects of aging. One may need bigger fonts and a case light, and the other may need bigger fonts plus a backlit screen.

Of course, only your mom knows. Taking her to Best Buy or something and just letting her try various demos might be a good idea.

OP, if you're worried about user friendliness or the set-up, don't be. It's really simple to set up an ereading app. In Android, I just opened the Marketplace and typed "ereader" into the search and it gives me all the apps. Or you can search for a specific app if there's one you think she'd like. Download, and then go get books. Done. You can stick the app icon on the homepage so it's the first thing she sees.