I’ve noticed this problem a lot recently. My phone will be somewhere where it’s struggling to find a signal, I’ll stick it in my back pocket, and 20 minutes later, I’d bet money you could crack an egg and fry it on its surface. I found a Techquickie video that explains this phenomenon. The video said the reasoning behind this overheating problem can be all thanked to the Second Law of Thermodynamics. This means that whenever energy is used, some of it becomes waste heat. Then, the video starts to get a little more technical. Inside a phone’s CPU, there are hundreds of tiny resistors that allocate power in the electronic. They ensure the right amount of power is distributed in the electronic, because if too much power is given, it can cause the electronic to function incorrectly or even damage the electronic. The power that is capped off has to go somewhere, right? Well that extra power is transformed into heat. Lots of resistors equals lots of extra heat. This is why there are fans inside the systems unit, to cool the CPU and prevent it from overheating. I mean, think about it. Computers juggle multiple tasks at once, and with all this energy, heat is produced. This all makes sense to me now.