Yeah, I think the differentiator here is definitely being able to push data from the device back to Home Assistant. Sure, there are other third-party apps that can do this already, or you can even roll your own setup with something like Tasker, which is the route I’ve taken. But for those who are less tech-savvy or don’t want to deal with the hassle of that, having an officially supported solution is a big plus.
That, and as I think someone mentioned upthread, for a lot of people, the first thing they do when looking at a piece of software is look for a mobile app. I agree that responsive websites with homescreen shortcuts are a great way to go when feasible, but a lot of people aren’t necessarily aware of this option or just have the idea of standalone apps ingrained.