Explained | SIM vs eSIM vs iSIM

Mobile phones have changed, their forms have changed, even their operating systems have changed. But we haven’t stopped relying on SIM cards. Yes, the shapes have been getting smaller and smaller but the core remains the same, literally. However, that may not be the case always. Enter eSIM. This new tech has been gradually making inroads on new smartphones. The tech is still not broadly available in smartphone sold in India. But we have already got the next big thing: iSIM.

Now let’s decipher this tech that you hardly see but are truly dependent on:


A SIM is short for subscriber identity module or subscriber identification module. Got it? Don’t worry, we are not leaving you with that shallow explanation.

A SIM card is how a telecom company identifies you and your smartphone. It is a unique identity, one that cannot be copied (in an ideal world). The SIM allows you to use some of the most basic functions of a smartphone, including calls, messages and even to access internet. A smartphone can survive without the SIM but it isn’t really a phone without it.

SIM cards have been gradually shedding excess weight. Old phones and smartphones used the complete SIM card. However, it was later cut down to microSIM and then to nano-SIM. Nano SIM card is currently the most used format.


Climbing up to the next step in SIM evolution. eSIM is something you might have never even seen. That’s because it is a part of your smartphone when you buy it. It isn’t something you can remove from your device. An eSIM or an embedded SIM does not need to be taken out of the device.

But what happens when you switch to a new phone?
Don’t worry, eSIMs are re-programmable and they can essentially take up another unique identity. You can easily disconnect any existing SIM identity when required and reconfigure another eSIM if needed.

Why eSIMs: SIM cards can only be cut as small as a nanoSIM. The provision of using an eSIM provides smartphone manufacturers with more space for other critical components such as the camera modules and battery.


To put it simply, iSIM is to eSIM what eSIM is to SIM. Well, not that simple? iSIM is an even smaller SIM. Companies are now integrating SIM within the main chipset of the device. An eSIM requires a separate chip whereas with iSIM this is no longer necessary and removes the need for dedicated space assigned to SIM services.

This level of integration allows more space for other components. Another major benefit is the optimization levels are very high compared to even eSIMs. This allows higher performance and increased memory capacity.

iSIM is proposed as the ideal solution for IoT devices and other products that will need to communicate at all times. The tech will take the mobile experience to laptops, tablets virtual reality platforms, IoT devices, wearables, and more.

Original Article