Hello @Lulu. I recently helped a shut-in senior myself. She had a newer donated iPhone and an iPad. The iPad was way out of date: only iOS 9, and no further OS updates possible! The iPhone was able to update right up to the latest (current) iOS 13.
There were all sorts of rigamaroles to go through just to update the phone, and install Signal and (regrettably) Zoom. We had to enter the iTunes password like 10 times. For all the dozens and dozens of annoying hoops that Apple made us jump through, I thought to myself, “this is not any simpler, nor easier than if this were just a Linux desktop”!
It took me like 1.5 hours just to install an OS update, and install 2 apps, for all the EULA’s, etc that we had to slog through. We wasted no time, and got right down to it. That senior would be precisely just as stuck on a linux laptop setup (requiring just as much help from someone like me), than on those Apple devices!! Contemplate that! The ease of installation which Apple products assumedly have ended up being worth nothing, since my help was needed at every step of the way!!
BTW: After playing around with LineageOS myself (and getting into some serious trouble, despite following the directions perfectly, requiring a total, desperate “unbricking” back to the stock Android), I don’t recommend it for seniors. If some update doesn’t go well, they won’t be able to bail themselves out with some rescue sideloading, etc.
If LineageOS was mature enough that it was installed on >=10M devices, I would say, yeah, that’s the kind of maturity I trust to go into the hands of seniors. But Lineage might have, what, like a few hundred thousands installs? So I can’t recommend it, as the community just isn’t big enough to ensure adequate smoothness.
I think you would rile the troops to your cause if you somehow came up with the money to buy a big pallete-load of, say, Lenovo Thinkpad X250s (or x230’s), and maybe put in refurbished batteries if necessary (as those older machines are actually designed to be sensibly serviceable, and can be used much longer than the throw-away mobiles of today).
Then hopefully something like Ubuntu (which has in the neighborhood of 10M installs) would be simple enough for those seniors (with auto-login upon boot). Why can’t an old person use a laptop? I don’t buy the rationale that they must have a mobile device. Surely they have at least a kitchen table to set the laptop on. And they can hopefully still lift 5 lbs. You know, about the weight of a full kettle to make tea.
PS: I think the current rule of thumb for older OS updates on mobile devices sort of goes like this: whatever the current version of Android/iOS is: don’t settle for less than the very current version, or up to 2 versions old. So for Android, only devices that have 10, 9, or 8 are really worth your while. Any older than that, and likely the security updates are so out of date, that it’s a hacker-prone gamble not really worth taking. Online Seniors get preyed on by hackers, on a regular basis. Please don’t make it easy for those hackers, just to save a small amount of money.