I wanted a 4" screen, and I'm very glad it's 4". I love the extra size, but any larger and I wouldn't like it. It's just at the border of one handed usability for me right now, and is slightly more awkward to use. Even a 4.2" would be enough to push me over the edge. And yes, I'm saying that if the 5S is a 4.5" device, I will not upgrade.