My Iphone 4s keeps shutting down?
My Iphone 4s version 5.1.1 keeps shutting down every few minutes and opens with it self, and it happened all day long so i turned it off for few hours and opened it after then but it kept doing the same thing and the battery kept going from 48% to 70% and then after 10% so i waited till the battery dies, but when it came to 1% it made the same thing and turned off without turning on again so i should have saw when it turned off that i need to plug the charger in but i didn't see it so i just plugged the charger in and it went to 100% while opening it so i removed the charger and kept happening all over again… So is there anything i could do to make my phone work normally or know were the problem is?
Added (1). I don't want to update the software because it will delete everything on my Iphone.