the issue has been shown on here in a few threads
my first i4 - the photos were all very yellow (both front and back camera) and a big green circle appeared on every photo
2nd - photos were a bit better - but same green sphere
3rd one is good - great quality photos. BUT - it seems now that it's a know issue that under some fluorescent lighting that there is a greenish haze in the photos. In low light, it's more reddish. The reddish though disappears if you use the flash.
In normal light or flash - all seems to be good