Well yes it is perfect... for one handed use and very pocket friendly. Also great for phone calls. The new iPhone is a bit harder to use one handed than the older iPhone but still far better than those huge Android phones. But while one handed use in applications is great, people don't use these things for phones so much anymore. From 2007 to now they have become more like little computers which was Jobs vision. So times have changed.
Now that they redesigned iOS 7 to go back and forth in applications using swipes rather than a back button at the top, the tall iPhone 5 is going to be "perfect" again for one handed use. But then the iOS 7 navigation redesign also means that they can go to wider phones without as much of a hit in usability since you can always swipe no matter how wide the phone. Interesting times ahead I say...
Not really.
I can see the note being not so one handed friendly but the gs4 is perfect one handed.
Android phones aren't "huge" and aside from the phablets they do fit in pockets