My experience is similar, but my grandmother has gotten worse at using her iPad as iOS has gotten more and more confusing. I usually see her with Safari in split-screen as Gruber mentioned, and know that: A) there's not really any way to teach her to get out of it because the gestures literally require more precise movements than her fingers are capable of, and B) there's no way to teach her to avoid open Safari in split-screen mode, because I constantly do it myself accidentally too on my iPad.

The iPad used to be a really great device for her use case, but the more they add gestures which it's easy to accidentally trigger but hard (as in physically hard, requiring precise finger movements) to reverse, the worse it gets.