During Apple's quarter earnings call, CEO Tim Cook took a question on whether or not Apple would consider shipping an iPhone with a 5-inch display. The question is pertinent not only because of sporadic rumors that Apple was considering a larger iPhone, but because so many of the iPhone's top-tier competitors have larger displays. Cook began as you'd expect, praising the current iPhone 5's screen, "iPhone 5 has the absolute best display in the industry," he said. Cook then began a small session about what sorts of "tradeoffs" to into a smartphone display, including "resolution, color, white balance, reflectivity, [and] compatibility with apps."
"We would not ship a larger display iPhone while these trade offs exist."