eSIM installation guide
The QR-code and manual installation methods explained in detail.
⚠️ Before you start
- •Install the eSIM while connected to WiFi. You can install it in advance while still at home.
- •On arrival, set the internet to the new eSIM and turn Data Roaming ON.
- •Most phones run only 2 SIMs at once, so temporarily remove or disable other SIMs.
- •An eSIM can be installed on only one device.
📷 Install with a QR code
Prepare the QR code
Print the QR code from the email, or open it on another device.
Open Settings
iPhone: Settings → Cellular / Mobile Data Android: Settings → SIM Card Management
Add the eSIM
While connected to the internet, tap Add eSIM and scan your QR code to install.
⌨️ Manual installation
If you can't scan the QR, enter the SM-DP+ Address and Activation Code from the order email manually.
iPhone, iPad installation guide
Scan the QR code
Settings → Cellular → Add eSIM → scan the QR with the phone camera. ⚠️ If "eSIM Cannot Be Added" appears, restart the phone and try again.
Turn on Data Roaming
Settings → Cellular → select our SIM → turn Data Roaming ON
Set the data SIM
Settings → Cellular → Cellular Data → select our SIM
Check data usage
Settings → Cellular → Current Period Roaming — your usage is shown here.
Extra settings
If advised by support: Settings → Cellular → our SIM → Network Selection → turn off Auto and pick the operator. Examples: China — China Mobile, China Unicom | Japan — NTT Docomo | Korea — SKT
Samsung, Android installation guide
Scan the QR code
Settings → Connections → SIM card manager → Add eSIM → scan the QR. Or tap Gallery to scan a saved QR code.
Turn on Data Roaming
Settings → Connections → Mobile network → turn Data roaming ON
Set the data SIM
Settings → Connections → SIM card manager → Preferred SIM card → select our SIM
Extra settings
If advised by support: Settings → Connections → Mobile networks → Network operators → turn off Auto, pick the operator, then toggle Airplane mode. Examples: China — China Mobile, China Unicom | Japan — NTT Docomo | Korea — SKT
⚙️ APN settings
For a multi-country/regional eSIM, the APN should switch automatically when you enter a new country. If it doesn't, set it manually.
🍎 iPhone
Settings → Cellular → Cellular Data Network → APN
🤖 Android
Settings → Connections → Mobile Networks → Access Point Names
Enter the APN details and restart your phone.
🛠️ Common errors & fixes
❌ "eSIM Cannot Be Added" / "Mobile Plan Cannot Be Added"
This error is usually caused by one of the following:
1. Two SIMs are already active
Most devices run only 2 SIMs (SIM/eSIM) at once. If two are active, adding a new eSIM triggers this error.
🍎 iPhone
Settings → Cellular → select an unused SIM → Turn On This Line → Off. Or Delete the old eSIM and re-install the Datasim eSIM.
🤖 Android
Settings → Network & Internet → SIMs → disable an unused SIM. Or delete the old eSIM and add the Datasim eSIM again.
2. eSIM storage is full
Some devices store 5–10 eSIM profiles. If old ones aren't deleted, new ones won't add. Delete unused eSIMs, restart the phone and install again.
3. Installing one eSIM too many times
Some eSIMs have an install limit (often up to 5). Exceeding it causes an error. Review each step in advance and avoid repeated attempts.
iPhone: eSIM installed but no internet
If the eSIM installed successfully, the network name shows and Data Roaming is ON but the internet still doesn't work — it's very likely the iPhone Limit IP Address Tracking setting.
✅ Fix (step by step):
- 1Settings → Cellular / Mobile Data
- 2Select your Datasim eSIM
- 3Open Cellular Data Options / Data Mode
- 4Turn Limit IP Address Tracking → OFF
- 5Toggle Airplane Mode ON/OFF (or restart the phone)
💡 On iOS 15, 16, 17, 18 this is one of the most common reasons data fails, together with VPN or iCloud Private Relay. Most iPhone data issues are resolved after setting Limit IP Address Tracking = OFF. Also double-check that VPN and Private Relay are off.
❌ "Unable to Activate eSIM"
If the eSIM installed but won't activate, check:
- ✅You have Wi-Fi or an internet connection
- ✅VPN is off
- ✅Your phone software is up to date
- ✅Your phone is not carrier-locked
❌ "Installation Failed"
Try these steps in order:
- 1Restart the phone
- 2Connect to Wi-Fi
- 3Turn off VPN
- 4Check for a software update
- 5If the QR fails, use Manual Installation
💡 If the QR fails, use Manual Setup. The required details (SM-DP+ Address, Activation Code) are in your order email.
Should I rename the eSIM after installing?
Yes. A clear name like "Datasim China", "Datasim Korea" or "Japan eSIM" avoids confusion when using several eSIMs.
Should I turn the eSIM on right after installing?
No. You can keep the eSIM off until you reach your destination. International data plans usually activate once they find the network in the destination country.
Can I move an eSIM to another phone?
No. An eSIM activated on one device can't be transferred to another.
🇰🇷 Korean numbered SIM / physical SIM
This works differently from a normal eSIM. No QR code arrives immediately — Korean law requires identity verification before activation.
1. Order and pay
Check your phone model is compatible first. If you choose a physical SIM you collect it yourself at Incheon Airport.
2. Send your passport details
Follow the link in your email: a clear passport photo, a selfie holding the passport, your name and number, and your Korea arrival date and time. Within 7 days.
3. Land in Korea
A numbered SIM only activates once entry to Korea is confirmed — roughly 2 hours after you clear immigration.
4. Collect / activate
Physical SIM: collect at your chosen Incheon terminal with your passport (10:00–19:00). eSIM: installation details arrive by email.
5. Receive your number
Once activated we email you the assigned 010 number.
⏰ Operating hours are 10:00–19:00 KST, weekends included. Requests outside those hours are handled in the next working window. Missing or unclear passport details delay activation.
🔒 Locked phone
If none of the above works, your phone may be carrier-locked. In that case contact your carrier to unlock it, then you can use the eSIM.