Very high iPhone temperatures can become a smartphone security issue. Here's what to do
If apps run slow, the camera is unresponsive, you experience screen problems and the iPhone gets too hot, the cause could be related to a malfunction of the battery or the hardware itself. The advice is to take the iPhone to an Apple Store or a service center enabled by the Cupertino company.
Unusually the not excessive temperature of the iPhone is not a problem, smartphones, unlike computers, do not have internal fans to be used to lower the temperature of the device, but disperse the heat through the metal structure that supports the body of the phone. Conversely, if your iPhone is too hot, it may break due to excessive temperatures inside the device. This could be a problem caused by the hardware, but also by software that doesn't run as it should.
How to fix it
If your phone easily overheats, try uninstalling the last apps you downloaded before the heat problem started to appear. Some apps may not work as they should, and it may result in the temperature of the processor being overloaded by the impossible tasks. If this method does not improve the situation, try to restore the default settings, but remember to back up your data on the phone using iCloud first. If all this does not help, the only thing you should do is to visit an Apple Store or authorized service center as soon as possible to solve the overheating problem for good.
How to cool your iPhone
To cool the phone and avoid any damage, you should remove the cover, unplug the charger and turn off the smartphone. Avoid blowing fresh air on the phone because too fast cooling may cause condensation inside the phone that could damage or destroy the iPhone's circuitry.