So far from what we have heard and seen about the iPhone 6s and 6s Plus is that for the most part, they work just fine. There haven’t really been any complaints, at least until recently when a Reddit thread revealed that there were some users who complained that their iPhones had been overheating.
As you can see in the screenshot, the overheating error message appeared when the user tried to launch the camera app. According to the original poster, “I’ve never had this problem with my 6 plus. I live in Tucson, but it was a cool 88°F at the time I was trying to take pictures. The phone hadn’t been used for anything intensive or demanding prior to trying to take pics, just cruising through Facebook randomly, and was stowed away in my back pocket mostly. I’ve noticed this phone, 6s Plus, has been the warmest to the touch of all the iPhones I’ve owned.”
This is pretty much the first time we have heard reports of the iPhone 6s overheating. Some comments in the thread have suggested that maybe background apps were to blame for the issue, such as Facebook which seems to be quite a battery drain meaning that its background process could also account for the phone overworking itself.
Some users have reported that this was an issue at the start when they were setting up their phones and syncing with iCloud, but once that was done the overheating seemed to have gone away. In any case it does not appear to be widespread so hopefully if you are planning on getting a new iPhone 6s that it won’t happen to you.