How clean master measure device temperature Clean master app latest version added the feature device cooler when CPU is overheating.

I want to know that how this app measure the temperature of device if there is no hardware support (sensor) is present in device? They are giving real time device temperature...

I want to know that how they measure this real time temperature of the device?
if there is no hardware support (sensor) is present in device


That's your mistaken assumption. Even dumbphones contain digital thermometers, to allow them to protect themselves against overheating when charging. Most smartphones will contain more than one temperature sensor: one in the battery, to detect if the battery is overheating, and one attached to the SoC, too see how warm it is getting under load. The SoC temperature is needed for the phone to be able to power-manage correctly, and to underclock the CPU and GPU if they're getting too hot.