Guys, i wanna ask something, is common for lumia 920 to reboot itself when the fon is hot?

Juz now i try my fren's lumia, he said when too much apps open, need to reboot, becoz i try to launch camera apps, but somehow showing loading only, n force close, try many times, end up he off the fon, n wait for few minutes before switch on again...please advice as i want to buy this fon so badly..