eSIM Installation Guide
※The following steps are for adding and activating a new eSIM profile on an eSIM-compatible smartphone without replacing the physical SIM. Please confirm in advance that your device is "SIM-unlocked/eSIM-compatible."
Common Preparation (iOS/Android)
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Confirm Compatible Device and Network
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Check that your device supports eSIM (model number, OS version, carrier restrictions, etc.).
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Your smartphone must be in a "SIM-free" state (not locked to a carrier), or allow eSIM use from external carriers.
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For overseas use, it is recommended to ensure an environment (Wi-Fi, etc.) where you can install and activate the eSIM profile before departure.
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Prepare QR Code
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Prepare the "QR code for eSIM profile installation" sent by the eSIM provider. The QR code should be readable in any format (paper, email, PDF, etc.).
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A stable internet connection (Wi-Fi, etc.) when scanning the QR code will make the process smoother.
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Confirm Physical SIM/Communication Settings
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Decide in advance whether to continue using your existing physical SIM or add a new eSIM as a secondary line, and how to use each (calls/data) to make setup smoother.
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It's reassuring to check roaming settings, data communication settings, and airplane mode activation before departure.
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iOS (iPhone/iPad) Instructions
Prerequisites
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iOS 13 or later (varies by model) with eSIM support.
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Use the "Settings" app.
Steps
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Prepare QR Code
- Have the QR code from your guide email/PDF ready to display (e.g., on another device's screen, printed material, screenshot, etc.).
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Open the "Settings" app → Go to "Cellular" or "Mobile Data".
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Tap "Add Cellular Plan" or "Add Plan".
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When a menu like "Install using eSIM" or "Use QR Code" appears, the camera screen for scanning the QR code will be displayed.
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Scan the QR code with your smartphone camera.
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After scanning is complete, the cellular plan profile will be downloaded and prepared.
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Confirm and set the plan name, line type (primary/secondary), default voice, data, and roaming settings.
- For example, set "Use secondary line (eSIM) for data only" or "Continue using physical SIM for calls + text" according to your needs.
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Tap "Add Cellular Plan" to confirm the profile.
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After the cellular plan is added, go to "Settings" → "Cellular/Mobile Data" to confirm the following for internet communication (including data roaming):
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The target eSIM line is "ON".
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"Data Roaming" is ON (for overseas use).
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Select "Default Line" and "Line to Use for Data" according to your needs.
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Restart the device if necessary.
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Confirm that communication is possible (internet browsing, etc.). It's reassuring to test whether data communication works at your destination by turning off Wi-Fi.
Additional Notes
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After adding eSIM, if you continue using the physical SIM, clearly setting the purpose (e.g., "calls/SMS" vs "data") will improve convenience.
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For eSIMs used overseas, completing installation before departure is recommended, as communication is often possible immediately upon arrival.
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Keep Wi-Fi connected while the installation process is running after scanning the QR code.
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The UI for switching "Primary Line" and "Secondary Line Activation" varies by device, so it's reassuring to familiarize yourself with the setup procedure.
Android Instructions
Prerequisites
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Android 10 or later, or an eSIM-compatible device/OS.
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Steps may vary slightly by manufacturer (Samsung, Google Pixel, Xiaomi, etc.).
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Here we explain the general flow, but please also check your device's manual or official website.
Steps
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Prepare QR Code
- Similar to iOS, prepare to display the QR code from your guide email/PDF.
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Open the "Settings" app → Go to "Network & Internet" or "Connections & Sharing" or similar.
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Select "SIM Cards/Mobile Network" or "Mobile Network" → "Add eSIM" or "Add Cellular Plan" or similar menu.
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Tap "Scan QR Code" or "Load eSIM Profile" and scan the QR code with your camera.
- After recognition, the eSIM profile download and setup will start automatically.
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When an option to "Activate" or "Start" the line appears, grant permission.
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Confirm and set the line name, purpose (e.g., data only/calls and data), and priority line settings.
- It's easier to organize by separating purposes, such as using the main line for physical SIM and the newly added eSIM as a secondary line.
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Set "Data Communication Line" and "Mobile Data Roaming":
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Set "Mobile Data" to use the eSIM line.
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Turn "Roaming" ON if necessary.
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After setup is complete, enable the eSIM line and restart the device, or confirm that communication is possible.
- Turn off Wi-Fi and test whether internet connection is possible.
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For overseas use, it's reassuring to complete activation before departure.
Additional Notes
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The screen for switching "Default Line" and "Priority Line" varies by Android device. Look for terms like Settings → Line Management → Priority Line.
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If you keep the physical SIM, clearly set which line to use for calls and which for data.
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After eSIM installation, you may need to check "APN" auto-loading/manual settings in the device's mobile network settings. Follow the provider's instructions.
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We strongly recommend installing and testing communication in a stable Wi-Fi environment before departure (to prevent cases where communication is not possible immediately upon arrival overseas).
Troubleshooting & Tips
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If QR code scanning doesn't work or shows an error:
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Try adjusting the camera focus.
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If the QR code screen is too bright or reflective and can't be read, use another screen or printed version.
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If the QR code is old and expired, request reissuance from the provider.
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If the line doesn't activate or communication doesn't work:
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Check if eSIM is "ON" and which line (physical SIM/eSIM) is prioritized.
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Check if data roaming settings are "OFF".
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Check if airplane mode is disabled.
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Check if OS and carrier settings are the latest version.
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Check if the device is "SIM-free (unlocked)".
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Notes for overseas use:
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It's reassuring to complete installation and activation before departure. If communication is not possible at the destination, it may cause issues with maps, transportation guides, hotel check-ins, etc.
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Check data usage and remaining balance frequently, and understand whether additional charging is possible.
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For "data-only eSIM" without calls/SMS, you should prepare a separate line for services that require SMS authentication or calls (banks, shopping, etc.).
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Note that eSIM reissuance is not possible if you lose or replace your device.