For me, it's definitely the widgets.
I know the most Apple guys (say) they don't like it (at this point), but I think it's a large part of the 'dated' comments and user experience. Nothing like having a single screen that I can put what I find relevant to me pinned to it and can be seen at once glance.
Yes - some guys go overboard, but I have only 3 pages : calendar on one page, and the other page data use, alarm, shares etc I don't have launches or 10 million things, but the basic are great. For me those basic make iOS dated.
I mean they didn't have notifications until recently, which was a ball ache compared to Android