An eSIM is a SIM card already embedded into your device, be it your mobile phone or a wearable device like smartwatches, which can support multiple mobile services via what is called a profile. This profile stores all the services you are subscribed to, as well as your network settings without the need for a traditional SIM card.

Additionally, you can combine an eSIM with a physical SIM card, giving you the flexibility of having a dual-SIM solution.