So have had my iPhone 6 for a couple of days now and have noticed when reading articles e.g Wikipedia, that when reading from left to right in portrait mode in going from yellow to white. It's quite faint and to be honest I can't notice it when I have a pure white screen, but as soon as the text is overlaid I notice it. I'm not really sure what to do, the phone is perfect other than this and I purchased AppleCare+ yesterday. I don't particularly want a replacement already as it'll be refurbished and I've only had the phone for 4 days. Maybe I'll have to return it, get a refund on AppleCare+ and then buy another?