The transition from physical SIM cards to embedded solutions has changed the mobile communications market forever. But even if the most tech-savvy users have gotten used to eSIM, the term iSIM still raises more questions. How are they different, what role do they play in the future of technology – we’ll figure it out in this article.
What is eSIM? Embedded, but not quite invisible
eSIM (embedded SIM) is a chip that is built into a device at the manufacturing stage. Unlike a classic plastic SIM card, eSIM cannot be removed, changed, or lost. But it performs the same function: it allows the device to connect to the operator’s cellular network.
Key features of eSIM:
- Physically located on the device’s motherboard
- Allows multiple operator profiles to be loaded
- Supported in over 200 countries
- Activated via QR code or app
According to GSMA, in 2025, 1 billion devices worldwide support eSIM, and by 2030, this figure could exceed 8 billion.
What is iSIM? The next evolution of connectivity
iSIM (integrated SIM) is a more advanced version of eSIM. Unlike the latter, iSIM does not require a separate chip: it is integrated directly into the device’s CPU or modem. This means less cost, less space, and more possibilities.
Features of iSIM:
- Fully integrated into SoC (system on a chip)
- Allows for simplified device design
- Provides a higher level of security
- Opens the door to mass adoption in IoT and wearable electronics
According to Counterpoint Research, devices with iSIM will appear in the mass segment by 2027.
Comparison of eSIM and iSIM
| Parameter | eSIM | iSIM |
| Physical implementation | Separate chip | Integration into the processor |
| Security | High | Very high (at the SoC level) |
| Power consumption | Average | 20–30% lower |
| Size | Smaller than nanoSIM | Even smaller, no separate chip |
| Flexibility | Support for multiple profiles | Same, + more adaptability |
| Mass distribution | Already implemented in smartphones | Limited for now, but growing rapidly |
Why is this important for users?
Mobile communications revolution
Devices are becoming more compact, more productive and more autonomous. Conventional SIM cards have long been a “brake” in the evolution of gadgets. eSIM freed manufacturers from a physical slot, but iSIM went further – it completely eliminates the need for a separate chip, which is especially important in the era of wearable devices and IoT.
iSIM allows you to embed mobile communications in any gadget, from smart watches to drones and electric cars. This is not just comfort, it is a new digital ecosystem.
Benefits for travelers and digital nomads
For those who often change countries and regions, eSIM and iSIM are a real find. You can literally connect to a local operator in minutes, without looking for a physical point of sale or opening a SIM card slot.
This is where Yesim comes to the rescue. Yesim.app is an international service that provides virtual SIM card connections in more than 150 countries. All the user needs:
- Install the Yeffsim app
- Select eSIM data plans (per-minute, daily and monthly plans are available)
- Activate eSIM in a couple of clicks – without visiting the operator’s office
Security and challenges of iSIM: a step forward with a look back
One of the main advantages of iSIM over its predecessors is considered to be a high level of security. Since iSIM is integrated directly into the device’s processor, it receives additional protection at the hardware level, which significantly complicates unauthorized access to data or hacking attempts. The absence of a separate chip eliminates physical intervention, and the built-in management system allows for centralized firmware updates and access control. That is why iSIM is considered an ideal solution for critical devices – from financial terminals to medical sensors and smart cars.
However, despite the obvious advantages, the mass implementation of iSIM still faces a number of obstacles. Telecom operators are in no hurry to adapt the infrastructure to new standards, and device manufacturers need to restructure their approach to chip design and architecture. It is also necessary to revise certification and compatibility schemes – after all, we are not just talking about a new SIM card, but about a fundamentally different communication logic. Many existing devices cannot technically be adapted to iSIM, which slows down scaling.
So iSIM does represent a technological leap forward, especially in terms of security and compactness, but its path to widespread adoption will require time, standards and cooperation from all market players.
Making a choice in 2025
The choice between eSIM and iSIM today largely depends on specific needs and available devices. If you already use a modern smartphone or tablet with eSIM support, this is the best and proven option, which gives flexibility when changing operators, especially when traveling. iSIM is the technology of the future, and at the moment it is available mainly in pilot projects or in niche IoT devices. Those who value advanced solutions, processor-level security and maximum compactness should keep an eye on the development of iSIM – in a few years it may become the new standard. But for now, eSIM remains the most universal and affordable choice for a wide audience.
Final say
eSIM and iSIM are not competitors, but stages of the same technological evolution. If eSIM is already a reality, then iSIM is the future, which is approaching faster than it seems. They make mobile communications flexible, safe and universal.
And services such as yesim.app already allow you to take advantage of eSIM without unnecessary bureaucracy. True freedom begins with a virtual connection.
