Aside from how painful that sounds, paper notepads can easily get lost. And if she's out and wants to check stuff on her phone (or trying to check her bank account at my aunt's home, or whatever), is she supposed to carry it all around and risk getting it stolen? If that's the implication, I'd rather she just have kitten4 at that point.
(And re: the grandma thing: it's nothing specific to grandmas, it's because the moment you suggest your audience is "college educated developers in their twenties" as in your case, people throw the notion of UI/UX out the window and recommend you suggest they compile their own kernel first. It seems you just can't win.)