Updating sim card
Typically the SIM lock is in exchange for a subsidized phone (so you can't buy a cheap phone on one carrier then switch over an use another before you've paid back the subsidy over the life of your contract). While customers have to pay more upfront for an unlocked version of the i Phone, they can use the phone with any compatible SIM card, as long as the phone works with that carrier's network.These days, Apple sells the i Phone SIM-unlocked in most countries, including the U. The latest i Phone, the 6s, supports 23 LTE bands, which comprises most of the world's carriers.SIM cards are the unseen magicians of today's smartphones.They make connecting to networks and switching phones as easy as removing a small metal tray.Essentially, these two numbers tell the carrier that your phone is allowed to operate on its network and, once connected, should be billed for certain features.Beyond identification, SIM cards have several other functions. While they have maintained a relative thickness of just under 1mm, their surface area has steadily decreased, from the credit card-sized plates used in the earliest cellphones to the nano SIMs of today's devices.There are also adapters so nano SIM cards can fit into slots meant for micro SIM or Regular SIM cards.
It is also identified by the carrier with its International mobile subscriber identity (IMSI).Practically speaking, it is a middleman between two pieces of hardware: the phone's baseband chip, and your carrier's cell towers, allowing the two to communicate.SIM cards allow you to travel between phones with your phone number and data plans; when you upgrade to a new i Phone, the SIM card travels (as long as it is the same size).Because it has a small amount of memory and a very low-powered processor, the SIM card not only enables communication between the phone and its carrier, but stores information such as phone numbers, security data and more.