After 10 months of delays, the white iPhone 4 has arrived, and at closer inspection it turns out it's not only late, but also thicker than its black sibling. The difference is very small, 0.2 millimeters to be more precise, but it's enough to give headaches to some users who would find their cases wouldn't fit on the white iPhone 4.

Ryan Cash, who posted comparison shots of the two models on his blog, first noticed the difference in thickness between the white and black iPhone 4. He didn't measure the devices, but the difference is noticeable with the naked eye. Then, the TiPb blog took the measurements and elucidated the mystery: indeed, the white iPhone 4 is 0.2 millimeters thicker than the black one.

The difference, from roughly 9.3mm thickness of the black iPhone to 9.5mm of the white model, doesn't come from the steel frame of the device, but from the white glass part on the front of the device. Apple doesn't list any difference in thickness on its website between the white and black iPhone 4.

Apple did not explain why the white iPhone 4 is thicker, but this could have something to do with why the device was delayed for 10 months. In an interview this week, Apple CEO Steve Jobs and Senior VP Phil Schiller said the white coloring of the white iPhone caused issues with manufacturing the model, so the extra thickness could be a result of this process.

Those who don't use a case for their white iPhone 4 should have no problems with the extra thickness. But the situation is slightly more intricate if you want to use a case, as most of them are designed to fir snugly on the 9.3mm black iPhone 4. Initial tests indicate that Apple's bumper cases, and most cases that aren't subject to depth will still fit the thicker white iPhone 4, but if you plan on buying a case for your shiny new white iPhone 4, it would be best to check if it fits first.

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