It's tempting to identify the iPhone (and smartphones broadly) and that's not totally wrong. Yes, it replaces a bunch of discrete devices from times past reasonably well for most purposes: telephone, still camera, video camera, iPod/Walkman, voice recorder, GPS, etc.
But that's not really what makes a modern smartphone so transformative. It's doing all those things while being essentially ubiquitous, mostly always connected, open to an amazing ecosystem of apps that take advantage of the hardware capabilities, and with access to an amazing amount of online information.
Modern smartphones are great products for the most part but it's how they function as part of an ecosystem that makes them transformative.
It seems like very much a comment about the broader ecosystem being a bigger factor than an individual device.
The most common one is probably pointless redesigns. Outside of games, users usually aren't pulling up a particular app for the pleasure of using it, they just want to use it to accomplish some other goal with as little trouble as possible.
I feel much the same way about git.
I still think abut it frequently. It's true. It's a statement about systems - often the utility is what they enable, not thing "thing in itself".
Even deep into software development, this is true. e.. I really appreciate git and github, but I don't need to focus on becoming a "git maestro" , I just need to get by in git, because git for me "isn't the thing", it's just "the thing that gets me to the thing".
Likewise, we can make software for people who are clever, even brilliant in what they do but who don't care abut the details of that software because for them it's not "the thing".
1) https://www.youtube.com/watch?v=QeY_5n75zPM