Yellow tint on S4's screen The phone's screen has an annoying yellow tint. Is there any app that can fix gamma correction ? Or shall I return the phone and get another one ? Anyone else has this ?  

This picture is from XDA-Developers and explains my problem :
This sounds reminiscent of a "feature" that's present on the S III. Try going into the Settings. In the Device section, click Display, then in the Screen section, click Screen mode. You probably want to change it from Dynamic to Standard.

(Some of these things might be named differently on the S4, in which case please edit the new names into this answer.)