I use the default interface in browser primarily, but I use Boost on my phone as well as Voyager.

I'm an old school geek. To me, an "app" is basically software running on a phone (in that context), or perhaps software running on a computer (although typically I'd use "application" there, but it depends. A small "application" might be an "app"). I know this is not universal. But for example, to me, reddit or Facebook or Lemmy is not an "app", it is a "website" that you can access via a browser or an app.