Was on 8 Plus last year and upgraded to Xs Max this year, my biggest issue at present is the awkward gesture implementation to invoke reachability. Especially when apple themselves suggest people to ditch hamburger menu in favour of tab bar navigation. This makes it almost impossible to actually use the reachability feature, because every time the phone decides to select the tab bar item instead of invoking reachability. Also, apps with table View Controllers scroll the view instead of invoking reachability. And most apps use this. It’s a nightmare. I genuinely hope Apple changes the reachability gestures.