Tim Cook did an interview at the All Things D11 conference and spilled some details not only on the WWDC-bound iOS7 but also on why Apple keeps on making just one iPhone, as opposed to different variations of it.
Given the question on why Apple doesn't follow the same strategy it does with the iPod (making different sizes for different people) Cook answered that the iPod serves a different purpose with its various sizes. However, with the iPhone, that's not the case, as there are a lot more fine details that go into making it.
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According to Apple's CEO, many people take into consideration the quality of the display, its properties such as color representation, white balance, brightness and more. The screen size is not necessarily the key factor, as is the battery life and look and feel of Apple's smartphone.
"It takes a lot of work, a lot of really detailed work, to do a phone right, when you manage the hardware, software and services around it. We