Photo quality from a cellphone - or any camera for that matter - can be difficult for an individual to judge.  Few people have multiple examples of the same handset, and that means comparing the images produced is extra tricky.  Still, just like all iPhone screens aren't created equal, the cameras look to be pretty variable too. 

The two photos above - taken in the same place in the same light - were taken by two iPhones owned by a husband and wife; hers on the left, his on the right.  His photo shows a noticeable green tint.

A replacement from Apple - cue a "very concerned" employee at the Genius Bar - was in fact even worse, showing far more green tint than his first handset.  In fact two others have shown the same green tinge and magenta centre.  The obvious reason is different suppliers for the camera assembly.

How are your photos coming out?  Let us know in the comments if you've had any issues with colour reproduction.