One wonders did the late Steve Jobs had design input in the early design of the iPhone 6 and 6+ models. Given his mantra of being able to operate most of the functions of the phone with one hand, I'm not sure if Jobs would have approved going to the 4.7" screen size for the iPhone 6, even if the thickness of the phone was reduced.
It's impossible for me to imagine Jobs approving something like the iOS Reachability function. That's such a contorted hack, any good designer would stop and think, "if I need something that stupid in my design, I've probably screwed up something pretty basic". For that matter, while there have been some nice upgrades in iOS7&8 functionality, the whole 'flat' look & feel to the UI is so puke-tastic and poorly functional, it's hard to imagine Jobs approving that either. iOS6 & previous really had visually easy to understand and one handed easy to operate nailed pretty good, just like a PHONE should. Like others have said, Jobs & Ives were an unbeatable team, but Ives without Jobs, well...