Apple managed to get a new standard for SIM cards approved by the European Telecommunications Institute (ETSI) back in June, and today we see the result of that effort. The new nano-SIM is 44 percent smaller than existing micro-SIM designs, which may not seem significant in something already so small, but which could ultimately give Apple a lot more to work with.
When it comes to adding more battery or new radios to the iPhone, the key to getting it done is freeing up space taken up by other elements. The nano-SIM does just that, minimizing the key component’s internal footprint, which may help account for why the new iPhone manages to get battery life on par with its predecessor despite a larger screen and LTE built-in.
Once upon a time, there was talk of Apple replacing SIM cards altogether with a built-in solution integrated inextricably into the phone itself. That proposed change met with the ire of carriers according to France Telecom CEO Stéphane Richard, and so Apple went the route of the nano-SIM instead. Eventually, I’d bet Apple will still push for an integrated SIM, since in-case real estate will only become more valuable, not less.