I just got my 4s yesterday and finding that it is getting quite warm under normal use. For instance, typing several messages in a warm makes the phone warm enough that my hands start to clam up. I don't have a problem with my hands sweating. I've also had the phone in my pocket and feel the phone heating up, especially the side right under the SIM slot. Playing a game can also make it warm enough that is noticeable. Is this normal? Note: I had a 3GS before and never felt heat like this.