Help! iPhone programs shut down automatically!

Have some time had major problems with my iPhone 4S. 'm Not entirely sure, but think it was after I installed iOS 6th

The problem is that every time I go into any program / ​​app that freezes everything and you come back to the Home screen. It's not just apps but also whether to write sms for example. Everything that was done in the program / ​​app is then deleted. Sometimes you can not even enter the programs / apps and sometimes you can be inside a minute before it freezes. In addition, load it quickly out and the phone seems to work constantly (warmer than usual) even though I do not use it.

Have tried to find solutions, but nothing seems to work for more than a short period. Have tried:

- To restore the iPhone to its original settings in iTunes.

- Making a quick recovery, by holding down both the Home button + mute button for apple shows up.

- Install a new app.

- Reinstall apps (erase + install the app again).

- Restart the phone.

- Complete all updates available for my apps.

- Authorized to my iPhone.

What should I do? I'm really tired of it not working. All tips are welcome!