Chosen Solution
My husband dropped his iPhone 6 on its face/front (but it only cracked the glass screen protector - not the phone’s actual screen - phone was in a protective case also). The back of the phone got really hot and now it won’t turn on. Suggestions? Is it possible the battery just needs replaced now? The phone is only a year old.
If it is less than or close to a year you may want to consider taking the phone to an Apple Store. It would probably cost less and save time, if the phone is damaged it would give you more options. I only say this because I had a phone die and was due to the circuit board, apple swapped it out for me. If you are determined to figure this out, try plugging the phone into a computer to see if the computer recognizes the device. It could be possible the digitizer died. If not, open the phone and check for loose cables, could be possible a cable came loose and crossed a wire. The battery could of also have been shorted out.
Sounds like the battery is in trouble, especially since it is getting hot. Can you try plugging it into a lightning cable and then connect it to the power outlet? The connector to the screen could be dislodge somehow, shined a flashlight on the screen and see if you see any logos including the Apple logo. Hold on the power and home button for about 7 to 10 seconds and see if that turns it on.
Had this problem two days ago, dropped phone from height, then screen wouldn’t switch on and back of phone got boiling hot, too hot to touch, called my insurance company next day put in a claim, i took the phone to the shop to drop off for repair and low and behold when the lady in te shop tried to turn it on, it turned on and started working again, been 15hrs since and no further problems, so my suggestion is just give it 12-24hrs then try switching on again.