How to fix the purple tint issue on Lumia 930
Microsoft has acknowledged that some users who bought the new Nokia Lumia 930 in Northern Europe found their displays suffering from a purple tint mostly visible in grey colors found in pop-ups and menus when brightness levels are set to auto or low. The company assured that this problem has been taken seriously. The situation is being examined closely right now as sample units from Norway are being investigated in the R/D center in Finland.
Luckily this purple tint is most likely caused by a wrong color calibration rather than a serious hardware problem so the purple tint should be addressed soon.
Though Microsoft is aware of the problem and the company should find a solution soon (probably with a software update), you can easily fix the problem by going to the Display tools manually adjusting the colors.
Go to Settings -> Display -> and adjust Tint settings towards green until the purple tint disappears. This should remove (most) of the purple tint at low and automatic brightness levels.
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