A lack of UV protection was the reason for the nine-month delay in the launch, according to Apple's senior vice president.



From PC World:

Apple senior vice president Phil Schiller told All Things Digital that similar to humans, especially those with fair skin, white iPhones need protection from the sun's ultraviolet rays.

"It was challenging. It's not as simple as making something white. There's a lot more that goes into both the material science of it-how it holds up over time, but also in how it all works with the sensors," Schiller said.

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