Why Do Some Phones Heat Up Like They're on Fire?

Phones can get really hot when they're working hard. Think of your phone like a tiny robot doing lots of tasks at once, like running a game, sending messages, and playing music all together. When it's working so hard, the parts inside the phone start to heat up, just like how you feel warm when you run around outside on a hot day. If it gets too hot, sometimes it can even shut down or slow down.