Luckily I had backup plans for the Android, in case she didn't want to use it :) It was a test machine to see if she could even begin to find it useful, and I assumed it'd probably be good enough because hey, they're all the same these days.
That's the reason why I chose Android in the first place, assuming I could set the launcher and just make it dead-simple. I did a week or two of research looking into apps that might suit an old-timer. Big Launcher is great, but doesn't fix Skype because Skype's UI is a nightmare (contacts + favorites + recent? really? she has about four people she'd Skype. Why are the video/etc buttons so tiny? Yes obviously that issue will be on iPad as well.) Tried a couple photos apps to see which was best. Tried a couple mail apps. Get PPS from daughter, have to find tiny buttons to move to next slide of cat, rather than just swiping, so app closes and she misses half the pics. I've found websites dedicated to the elderly but none that seem to clear the whole mess up. While trying to do this, I'm listening to her talking to Google because she clicking something and Google says "Talk now", so she's telling it she can't find her email. They put in a quad-core processor so battery dies in no time. The Google tells me the mini has better battery life.
Home button disappears sometimes (e.g. camera, or Solitaire game) and replaced by tiny dot (so you want to go home but can't, or at least can't find it). iPad, it's always there - the physical round thing. Sometimes she touches the home/back buttons when typing (closes game or mail, very surprised - so now you don't want to go home but do), and iPad doesn't have soft buttons below the space bar. Send button is very close to the menu on Android. On iPad there are only two buttons and they're far from each other. Just above the home button Google has the "all apps" button, which she just doesn't need front-and-center. Back button sometimes does X, sometimes does Y, depending on context. Small USB cable works one-way only, iPad's can be inserted both ways. On this device can't remove the Google search bar near the top (I think?) and she's not quite ready for the web yet. Or Google's voice thing that didn't help her. At some point I need to take her off Google+ because she doesn't need any alerts that some random person is now following her. That shit is not in the user's best interests, it's in Google's. Then she's building up a great set of drafts because she'll edit and hit the wrong thing and it'll be gone, whereas the iPad app asks "Delete Draft? Save Draft?" when you click cancel. AFAIKT you can only hit "Send", "Cancel" or the hardware home button while writing a mail. Nothing else goes wrong.
Please don't assume your ten seconds on the problem has shown me to be an idiot. If you find a perfect setup, please tell me.
Btw her daughter and granddaughter both have iPads which helps the support situation greatly because they know what the button does. And shops currently have specials on the older non-retina, which is fine for her. We'll try it out and if she finds the Android better given her extra week of usage, that's a useful experiment. The money is very secondary compared to finding an experience that makes an old lady happy that she can "write letters to her friends". It's a game changer and she's enjoying it despite frustrations.
Current annoyance is that the toolbar icons on iPad can't grow with the fonts. Yes can use the Zoom but that's a bit crap. Will test it with her.