I read that both uses a different type of sim card. I have iphone 4s with a sim card that is bought here in mexico called telcel. I will most likely get the iphone 5s since i have lot of issues with my iphone 4s. I want to know, could i use the 4s sim card into the 5s? The reason i ask this is because i read online that you can do this if you cut the 4s sim card into a nano sim card... then plug it into the 5s. Is this true or not? I would prefer this not only because i dont have to buy new sim card... but because i want to keep my number and also my credit from this phone. Thank you.