Unfortunately it seems there is reluctance in getting replacement devices for people who are having excessive heat being generated by their phones. What suggestions come to mind would be the following:
- If at all possible use a thermometer gun when your phone gets hot to get a solid data to be able to present to Apple reps. If you don't have one, I just searched "thermometer gun", and saw some in the $20 range. I am sure there is software that will give the running temperature, but if you are already suspecting the device to not be running properly, an independent means of measurement would help eliminate that potential inaccuracy. This on its own will help you know better what you are experiencing, and if going to Apple reps, you would be able to eliminate the subjective "what is hot for one person might not be hot for the next" type of thing. Though all electronics will generate heat, their ability to effectively dissipate it is what will help keep your device working the best in the long run.
- Write/record when you notice it getting hot (date/time/location of phone/surrounding temperature/phone temperature/apps running at the time/case on the phone/charging or not/etc.) until you get maybe a few days or a weeks worth of data. It should help in identifying potential additional factors/causes if there are any. Again this will help if contacting an Apple agent for diagnosing.
- Try a different Apple repair location and see if you get any different answers from talking with someone else. Sometimes talking to a different person will make all the difference as well.
From reading the different experiences people have had with their devices, interactions with support, feedback from different users in multiple forums, I think that recording some data to use when reporting the problem will help in getting away from a fairly common first tier support assumption that the user may be a little overly sensitive, not using the device properly or not correctly remembering events/details (first tier support is typically the first representative you speak with, which is able to diagnose/fix/filter most of the reported problems). Taking the extra time to get this kind of info ahead of time may help avoid headaches when trying to get help. The phones are supposed to shut down to avoid catastrophic heat failures, same as their are supposed operate at a certain level of performance. Just because your phone does not continuously shut down due to high temperatures, it does not mean that it is working at the desired (user and/or manufacturer) level of performance.
I hope that this may be of help to you or anyone looking for help. Unfortunately it isn't a guaranteed way get something immediately repaired, but it should help either get you the additional data to make your case, or figure out if something else may be to blame.
