How can I prove that my iphone 6 overheats?

My phone overheats and it caused the screen to crack. I was holding it when it happened. Nobody believes me, so I want to prove it.

No way to really prove it now if you were the only witness. If you're generally a trustworthy person those who know you will believe you. The Apple folks..may be suspicious if this isn't a known issue. If it's a known issue no problem. Try to find other people that had this issue and you're more likely to be believed.

Also, if you can recreate what happened for whomever you're trying to prove it to, that will work. :)