What comes after eSIM? Introducing the iSIM

The eSIM has been the talk of the tech town in the last year, even becoming a household term thanks to the iPhone 14. Businesses are increasingly looking to leverage eSIMs to power connected devices and IoT solutions. Juniper Research predicts the eSIM market will be worth $16.3 billion by 2027. But don’t be deceived, for another SIM is ready to make a big impact in the market – the iSIM or “integrated SIM” is coming…

Are we moving on from the eSIM already? 

I know what you’re thinking, the eSIM has only just arrived and we’re already moving on to the next thing!? It’s true, we’ve been waiting a long time for something to come along and disrupt the classic SIM card, which has been in situ since the early 90s. Now we have two arriving in the market in a reasonably short time span. But both of these SIMs are just starting their journeys and could coexist for many years. With that in mind, what’s the difference?

The eSIM or “embedded SIM” is integrated permanently into a device, avoiding the need to replace the SIM in order to change the network provider. And it can be done remotely, which not only means the industry can manufacture fewer SIM cards, but it’s also more flexible for businesses and consumers.

The iSIM or “integrated SIM” also has this benefit, but the key difference is that the iSIM is almost not a SIM card at all. Instead, the functionality of the traditional SIM is integrated directly into the device’s central processor. While in theory, the iSIM could eventually completely replace the eSIM, this is a long way off (if it happens at all). Since an iSIM is fully ingrained in its device, developing them is more complex and time-consuming, making it less “off the shelf” than a normal SIM or eSIM. Because of this, manufacturers may at times prefer the eSIM for quicker time-to-market.

Mini, Micro, Nano – gone! 

So why would a manufacturer choose an iSIM over an eSIM? The “biggest” difference is size. Because the iSIM is part of the device’s CPU, it can be 98% smaller than an eSIM. The size of SIM cards has always been a key issue that new innovations in the space have tried to solve. Just cast your mind back to the development of the mini-SIM, micro-SIM or nano-SIM. The iSIM takes this to a new level by removing the “card” from the SIM entirely.

But why does size matter so much? Well, firstly it affects just what you can connect in the first place. iSIMs mean we can connect smaller and smaller devices, which is hugely significant for IoT and M2M use cases. Because they aren’t separate, dedicated components, iSIMs also have a smaller power requirement. In fact, an iSIM uses around 70% less energy than a normal SIM or eSIM. Their development can be more time-consuming and complex, but once it reaches the manufacturing stage, the simplified designs mean they cost half as much to actually build – due to fewer components.

Putting the I in IoT 

While these benefits for device manufacturers would still be significant even in a vacuum, what’s truly exciting is what it means for the bigger picture of global IoT or M2M communications.

Their small size opens the door to connecting more devices than ever, but with lower manufacturing costs and smaller power demands. That also has big implications for greater economies of scale. And scale is what IoT and Industry 4.0 are all about – if you’re connecting thousands of devices in a manufacturing process or individual spaces in a car park, reducing costs on each one of those connections is vital and will make more use cases financially viable as a result.

Perhaps just as crucially, iSIMs share the trait that makes eSIMs so valuable to IoT device manufacturers: the ability to swap to different networks and connectivity providers as needed. Use cases for this include devices roaming between networks, which could be internationally or between public and private networks. However, just how “smooth” these transitions are is something the industry is still working on perfecting. It also means connected devices can be created in one central factory and then provisioned with the local connectivity profiles they need once shipped around the world. With traditional SIM cards, you have to prepare different SIMs for each region, making the process more complex and costly.

While the question of whether iSIMs will ever completely replace the eSIM is up for debate, what we know for certain is that businesses building IoT solutions have got more tools at their disposal than ever. Manufacturing and setting up connected devices is now more simple, cost-effective and flexible. The upshot of this is that connecting everything and achieving “massive IoT” is finally on the horizon.

SIM technology is just one piece of the puzzle falling into place here alongside many others, including 5G, private networks, and satellite connectivity, meaning Industry 4.0 is no longer a pipe dream. The “smart cities” and “smart airports” that we’ve been promised for some time are finally on the doorstep, and the humble iSIM will be right at the (tiny) heart of it all.