Sister bought a Samsung Note 3 and gave me her S4. There was a yellow colour tint all over, specially noticeable on white. I googled for yellow tint on amoled screens for about two days. It was a fact. Whites weren't white indeed. I started to consider to give the phone back and get myself an IPS. Then removed the screen protector. Now most of the yellow tint is gone. So, beware.