Just like any other GSM phones, the iPhone uses a sim card that is used to store text messages and contacts and most importantly the details of the network provider. In order to replace a damaged sim card or even switching network service provider one need to know how to open iPhone sim card. One first identifies where the sim card slot of the iPhone they are using is located.
The sim card is usually located on the upper part unit of the phone located near the power button. The round jack port is for the earphones while the elliptical port is the sim card slot. Bend a paper clip in a way that it is straight and pointy. Insert the pin or the paper clip in the sim card slot of the iPhone. The pin or the paper clip should be pushed into the hole and the sim card drawer pops out a tiny bit. While pulling the sim card drawer out sing the index finger remove the sim card from the sim tray. One can then replace or make changes to the sim card before returning to the try and slotting it back to its port. One should learn how to open iPhone sim card to make any changes when need be in the future.