Few iPhone 4 users reported that they are facing some serious problems with their iPhone 4; One such problem was yellow pigmentation being seen on the retina display of iPhone. Well I was going through forum threads and  I found a legit explanation that why few iPhone 4 users are seeing yellow spot on Appleinsider forums:“Apple is using a bonding agent called Organofunctional Silane Z-6011 to bond the layers of glass. Apparently, Apple (or more likely Foxconn) is shipping these products so quickly that the evaporation process is not complete. However, after one or two days of use, especially with the screen on, will complete the evaporation process and the yellow “blotches” will disappear.
How do I know? I was involved in pitching Z-6011 to Apple”

If  above statement is true then this is not a serious problem. So if your iPhone 4 has yellow spot just use it for few days and do let us know the status if you see any improvement.

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