My iphone 4s get hot after using for a while, what's the problem?

My i phone get so hot after using for awhile, especially after surfing net and connect it to computer by turning on the hot spot, what does it mean? Does that mean there are some thing wrong my iphone?

This is a very common problem with the iPhone 4S. To be more sure you might try doing a "restore" but don't refresh via any backups. Essentially make it a default new iphone 4s without any of your content or settings. If it still drops Wi-Fi then Apple should fix it for you (i.e.warrantee replacement phone).

Do you use your iPhone while it's charging? This tends to make my phone hot

Nope, not at all. Nothing is wrong, it's just that using many applications at once or excessive use consumes more power hence the battery heats up.

It happens to many other brands of phone as well, for instance it happens to my Samsung and Blackberry

You overheated it, leave it alone for a bit to cool down. As a suggestion maybe cut down your usage a little bit

It means that the CPU has been working very hard. When a mobile CPU starts to run hot it drains battery life very quickly and hurts the battery. I'm going to guess the phone is already in a rather hot environment. Just Try to keep the phone cool for future us

You over-used it which means it'll over heat but no worries. Just place it near a fan or AC for 5-20 minutes.