I'm asking this on behalf of my boyfriend since he's not on here. Basically his 4S (originally AT&T, now T-Mobile) occasionally overheats when it's charging and has been having issues with losing the signal. He took it in to the Genius Bar, and all they told him was to restore it and redownload his apps. The diagnostic supposedly said it was working fine. Has anyone else had this problem? Is the only solution to hope a restore fixes it? Dependingn in what the 5S is like, he'll probably get that or the 5 this fall, but it'd be nice if the 4S would work properly in the meantime. Thanks!