Many Iphone4 customers have reported a yellow tinge to their pictures when taken in low light situations (when the flash is activated) If you do some research there will be a few areas that customers say cause that problem:-

Phone cases obstructing part of the camera lens

Phone screen and back covers causing obstruction

Finger too near camera or flash area

Bad Led flash components used in the manufacturing process

Although the above can lead to many other issues, this is not what causes the yellow look on photographs taken with the flash on. and although Apple have not confirmed this, we are sure this will be fixed with a software update in the near future. The issue lies with a timing issue between the shutter speed and the time at which the LED is activated for the flash.

Until then?

If you go to the App store, search for camera, you will see a result called camera plus, Its by Global Delight, and if you use this, your pictures will be a whole lot more natural looking