An Apple-proposed variant of the upcoming Nano SIM card standard is being shown off at the International CTIA Wireless show. Apple modified the design around Nokia’s concerns and ahead of the final vote tally, which is mere days away. Voting for members of The European Telecommunications Standards Institute (ETSI) began last month and wraps up in mid-May.

According to SIM card maker Giesecke & Devrient (G&D), the revised variant is being “driven by a supplier”, in this case Apple. So, how has Apple changed the original design to counter Nokia’s concerns? With a slight ‘how come I didn’t think of it’ tweak, that’s how…

Firstly, don’t count on the Apple-backed Nano SIM debuting on the next iPhone. Micro SIM took five years since ratification to appear in the iPhone 4. But don’t panic, Nano SIM could appear in devices in 2013, G&D hinted:

Adoption is being driven by a supplier. We’ll see a product very soon after ratification.

As for Nokia’s concern that Apple’s design – which originally called for a third-smaller SIM card with a tray – would require devices to be re-engineered with this in mind, Chriz Ziegler, writing for The Verge, explains:

A small amount of plastic has been added around the edges of the electrical contacts, making the new nano-SIM just long enough so that it can’t be forced lengthwise into an incompatible socket.

Though the modification saves little room inside devices, it nevertheless provides some additional space for other components compared to the Micro SIM it’s replacing.

More importantly, Nokia could no longer argue that Apple’s Nano SIM would makes it easy for customers to accidentally jam it into a Micro SIM slot. Let’s also not forget that Apple was granted a patent pertaining to so-called SIM connector, which lends itself nicely to Nano SIM.

A SIM card tray component leaked from a part supplier, shown below, also suggests the next iPhone will still feature a Micro SIM slot.

As you’ll recall, Nokia – with a little friendly help from RIM – is basically saying Apple’s variant is no good, accusing the iPhone maker of imposing the standard upon itself, Research In Motion and Motorola.

Apple on its part promised to license its Nano SIM to others on a royalty-free basis, to which Nokia threatened it won’t license essential patents pertaining to the standard should Apple prevail.

If Nokia’s proposal gets chosen, there’s nothing stopping the Finnish cell phone giant from extracting license fees from competitors.

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