A tiny chip inside your phone that stores your phone number and carrier information. Without it, no calls or mobile data.
Standard (old), micro (older smartphones), nano (current standard). eSIM is a built-in chip requiring no physical card.
No calls, SMS, or mobile data. Wi-Fi and offline features still work.
Don't lend your SIM to anyone. Report loss immediately. Set a SIM PIN code to prevent misuse if stolen.
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Yes, if the phone is SIM-unlocked. Phones sold after October 2021 in Japan are unlocked by default. Older phones may need carrier unlocking.
No. The SIM only stores your phone number and carrier information. Photos, apps, and contacts are stored on the phone itself or in the cloud.
Both work the same way. eSIM can be activated online instantly with no risk of losing the card. Physical SIM works with more devices and can be quickly swapped to another phone if yours breaks. If unsure, physical SIM is the safer choice.
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