Can we just move the iPhone's sim to a razr phone temporarily and it will work with his phone number? Hubby is going to be out in very hot weather (over 113) and the last time that happened his iPhone just shut down and wouldn't turn on due to excess heat until it cooled down. (dope) So I want him to use his old razr phone while he is out on the golf course. Will that work? Can he just switch back and forth like that with no adverse affect?