No, in this case App is not just a short name for application or a program, don't go into semantics. It's very different way they are coded and used. .
Windows ME was working for me just fine but yes XP was better because it took advantage of new HW better than W95 series. Not that there was no resistance to it when it was introduced.
I could also go on and on with good things in W10, better than in 7, personal preferences notwithstanding. There's a lot of room for improvement though but expected to be done sooner or later.