Does it happens on standby or when using a particular app? Mine only gets very hot when using as screen for my XSP-N1BT car stereo, playing music and navigating with waze/gmaps simultaneously... Otherwise it stay pretty cool
It happends with normal usage, browsing Internet on Google Chrome, for example. On stand by it is ok unless its charging. Right now it is plugged to the charger and the back is quite hot. My old xperia x10i used to get hot when charging but the Samsung galaxy s3 not. Thanks for your input.