Don't take this the wrong way, but it's obvious from this comment that you've never spent any time working with a blind person on an interface. This idea that a blind person would need tactile feedback comes from a sighted person imagining what it would like to be blind, not the experience of actual blind people with buttons vs touchscreens.

No offense taken, I am in fact just as ignorant as I appear to be.

This is just not as big of a problem as you think it is. Most blind folks I know rave about their iPhones and generally don't feel limited by it like they might have with their BrailleNotes or mediocre screenreaders/a11y tools on android. Many iOS apps also have a fairly accessible default state, assuming devs didn't go overboard with custom everything up the wazoo with no care for accessibility.

I used to work with some blind individuals, and one thing that's hard to relate to is how much more attention they give to things that sighted individuals do not, such as sounds, spatial relationships, etc. I wouldn't think they'd have any problem, for example, opening a specific app on their iPhone solely by its position on the home screen.

Wouldn't you just use Siri for that? I have enough apps that it's mostly too hard remembering where all but the most commonly used live, so I just tell Siri to open the app. Works like a charm.

You can get a physical keyboard for an iPad if you want one. Then you get a touch screen and a keyboard.