Back on Android, (or Windows, or Linux), it makes sense, whereas she loses her way. Just to point out, a part of discoverability I guess is familiarity with the underlying principles the UI follows as well.
To add two more points to this. I think there's one thing platforms in general got very right: simple touch controls. My one year old is discovering that sliding fingers across a screen, touching and pinching (the three basics) does stuff. Hidden menus, press-and-hold, and so on is secondary. Second, icons are something which is wrong. You need to guess their initial meaning, and translate badly in conversations, like recently with my mom: "press the rectangle with four arrows pointing out of it" (fullscreen or whatever it was).