"devices we use constantly, all day, probably some absurd number of times per hour"

So, they're like phones, then. ;) When I was a teen, my peers and I used our phones (some of them even were landlines) constantly. But the fashion attribute was minimal, and the functionality was pretty much identical regardless of brand.

Not that that kept me from feeling immeasurably cooler than everyone else when I got a nice and tiny Nokia 8290...