Getting more known - here's the best explanation from a photography site:
http://www.dpreview.com/articles/6867454450/quick-review-apple-iphone-5-camera/3
Remember - it's a phone first, a camera somewhere down the line...
I can see it can happen in a 4S but out of the hundreds of photos I took with the 4S I got no purple. With the 5 I have it in a number of photos already. This is not right to me.