My iPhone has been overheating lately while just laying idle next my pillow during the night charging, and losing battery faster then the charger is able to recharge it. I want to take it to the apple store and try to get a new one but last time they told me they can only exchange it if they verify the problem. Many times I've seen them using an app on their macs which lets them monitor previous battery usage times, dropped calls, etc. So I am wondering if they can also monitor highest temperature reached as well since we do know that an iphone has a temperature sensor. Or is there another way they can verify the problem.