The iPad Air 2 may be thinner than ever before and have the great new A8X processor, but there's one more feature that's definitely worthy of some praise. The Apple SIM.

The preinstalled Apple SIM comes with the iPad Air 2 and allows Wi-Fi and cellular connectivity. It even allows users to choose which carrier they want to buy data from. For now it is only on the iPad Air 2 and iPad mini 3, not on iPhones.

"The Apple SIM gives you the flexibility to choose from a variety of short-term plans from select carriers in the U.S. and U.K. right on your iPad," says the company on its website. "So whenever you need it, you can choose the plan that works best for you -- with no long-term commitments."

The new feature could, eventually, free people from the need to be stuck with one specific carrier. While currently it is a little more complicated than that, this is still a rather notable development.

The SIM supports 20 LTE bands, making the iPad Air 2 with Wi-Fi plus cellular great for traveling since it will make cellular data connectivity easier. So far only four carriers are on board with the new technology, although that number will likely grow. The four carriers that support the technology are AT&T, Sprint and T-Mobile in the U.S. and EE in the U.K.

"Apple is the only company that has the gravitas to be able to pull off this kind of deal. Other manufacturers will look on in complete awe, because it just further underlines the strength of position Apple has," said Ben Wood, director of research at CCS Insight.

Despite the innovation, many are wondering why the company did not introduce the technology in the new iPhone. However, it seems as though Apple wants to proceed with caution. It is likely that carriers will try to resist the new feature, but when it comes to tablets carriers have largely been unsuccessful at connecting users, so they really have nothing to lose.

"Operators see this as an opportunity to get more revenue by taking this more flexible approach. Because they have tried everything else and the reality is that it hasn't really moved the needle," continued Wood.

One of the great things about the new SIM is the fact that it removes a measure of control from the carriers. T-Mobile is a company that has especially been going after consumers, removing contracts and slashing prices. The company will be offering buyers of the new iPad 5 gigabytes of data that can be used for five months for only $10. This offer is only for a limited time, however.

It is likely that this new feature will put a lot of pressure on carriers, but only time will tell if it ends up being adopted in other devices.