There are some legitimate missing apps that seem basic on android, like led flashing for missed notifications. I bounce back and forth between the two platforms and am awaiting delivery of my 5S, but one of my favorite features is my S4 has an led on the front that flashes for missed notifications. Can even set it to different colors and flash rates for different notifications. The other is third party keyboards like swype or swiftkey. I use swiftkey and it has whole word predictions above the keyboard for the next word in your text, without waiting for a couple of letters of that word to be typed first.
Google Nav was another large missing piece, but they fixed that
.