FAQ

A SIM (Subscriber Identity Module) card is a small, removable card that connects your phone to a cellular network. It stores your phone number, carrier details, and authentication info. SIMs come in standard, micro, or nano sizes.

An eSIM (embedded SIM) is a digital SIM built into your device. It performs the same functions as a physical SIM but doesn't need to be inserted. You can switch carriers or plans without changing a card, making it ideal for phones, tablets, and smartwatches.

A SIM card links your device to the network and handles three main jobs:

1. Identification: Unique codes (IMSI and ICCID) tell the network who you are and which carrier to use.

2. Connectivity: Guides your phone to the correct network at home or abroad.

3. Storage: Holds a limited number of contacts and a few SMS messages.

A SIM card stores a small but essential set of information:

• Personal info: A few contacts and messages.

• Network data: IMSI, ICCID, and carrier settings for secure connection.

Tip: A SIM card does not store photos, apps, or most messages—those are saved on your device or in the cloud.

Yes, but the phone's functionality is limited. Without a SIM, it cannot connect to a mobile network for calls, texts, or mobile data. You can still use Wi-Fi for browsing, apps, streaming, and internet-based calls like WhatsApp or FaceTime. Phones with eSIM support can also activate a digital SIM without a physical card.

When you move a SIM card to another phone, your mobile number, carrier plan, and any data stored on the SIM (like contacts or SMS messages) transfer to the new device. The new phone adopts the identity and network settings of that SIM card.

eSIMs offer more convenience and flexibility. They eliminate physical cards, support multiple profiles, and make switching carriers easier. For frequent travelers, eSIMs allow instant local or international plans without buying a physical SIM. Physical SIM cards remain useful for simplicity and universal compatibility. The best choice depends on your needs, but eSIMs are generally considered the future.

Yes. Your phone number is linked to your SIM card through its IMSI (International Mobile Subscriber Identity). This allows your carrier to identify your account and assign your number. If you switch SIM cards, your number usually changes unless you request a transfer from your carrier.

Yes. Many modern phones support a physical SIM card and an eSIM at the same time, letting you use two numbers or carriers on one device.