Tried 6 iPhones, 4 black, 2 silver. All of them are the same temperature hot (didn't measure, but feels the same), when update from iTunes or warm, when download something. The hottest par is next to camera - power button. They all are ok at normal use.
Screens are also different from bluewish white to warmish white.
Screens are also different from bluewish white to warmish white.