Yet, she demonstrated she knew how a touch screen device worked. In this case, I have to guess it was the iPhone she knew how to operate since you ruled out the iPad.
The bottom line is your example disproved your own point.
If anything it shows the not so tech-savvy population adapts to or recognizes or is able to play with Apple's touch screen (iOS) devices rather well.
This isn't about touch screens. It's about tech knowledge in general. Yeah, she knows how a touch screen works, but there's no way she's going to know about the details of the iPad models.
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I think there is a cross-up here about the term "native app". Your tern of "native app" meant "application run natively on iOS devices" while others used the same term referring to "first party application pre-installed with iOS."
Well, others are wrong. "Native" does not mean that it's first-party. I've always seen it used to mean that it's compiled for that specific machine or something. Dictionary.com says:
Designed for or built into a given system, esp. denoting the language associated with a given processor, computer, or compiler, and programs written in it