Apple iPhones are offered by mobile phone networks which use Global Systems for Mobile Communications or “GSM” technology, which requires using Customer Identity Module or “SIM” cards. From the technological perspective, you’ll be able to make use of the same SIM by having an apple iPhone although certain conditions may stop you from doing this. For example if you are planning to make use of an apple SIM from the different network this may not focus on your overall apple iPhone plan or contract.
The type of your Apple iPhone would determine if you’re able to make use of the same Sim. So the apple model you use may stop you from having its SIM with apple iPhone. Particularly, the apple iPhone 4 and 4S use more compact “micro” Sims than previous models that don’t fill the SIM slot on previous versions from the apple iPhone. Likewise, individuals bigger Sims can’t fit inside the SIM trays of apple iphone 4 and 4S products.
Also iPhone 5 uses an even smaller version of the SIM card call Nano SIM which would stop you from swapping SIMs. There are other compatibility issues due to the launch of a new charger adaptor. So all your previous Apple chargers would become useless and you would need some time until cheap versions of the new charger appear in sites like Amazon or Ebay.