Why Use eSIM for Data and MyLine for Voice?

This Dual SIM strategy is popular among frequent travelers for good reasons:

• Save money: eSIM data plans (Airalo, Holafly, Nomad, Saily) are 70–90% cheaper than roaming for data-heavy use.
• Keep your number: Receive calls/SMS on your MyLine/home number for family, banking 2FA, ride-hailing verifications, or local services.
• Unlimited data freedom: Stream, navigate, video call over WhatsApp/WeChat without worrying about voice minutes.
• Seamless switching: Both lines active simultaneously (Dual SIM Dual Standby) — no manual swaps.
• Better coverage: Travel eSIM often uses multiple local networks; MyLine/home line stays reachable.

Setting Up Dual SIM on iPhone

iPhones (XS and newer) support multiple eSIMs + physical SIM.

1. Install your travel eSIM: Follow Settings → Cellular → Add eSIM → scan QR code from provider (Airalo, Holafly, etc.). Label it “Travel Data”.
2. Keep MyLine/home line active: This is usually your primary eSIM or physical SIM.
3. Set defaults:
   • Cellular Data → Select “Travel Data” eSIM.
   • Default Voice Line → Select MyLine/home line.
   • Allow Cellular Data Switching → ON (for seamless failover).
4. Enable Data Roaming on the travel eSIM only.
5. Test: Make a call on MyLine line, browse on travel data — both should work simultaneously.

You'll see both carrier names in the status bar. Incoming calls ring on MyLine line while using travel data.

Setting Up Dual SIM on Android

Steps vary slightly by brand (Samsung, Google Pixel, etc.), but core process is similar.

1. Add travel eSIM: Settings → Network & internet → SIMs → + Add eSIM → scan QR code. Label “Travel Data”.
2. MyLine/home line: Usually your primary physical SIM or eSIM — keep enabled.
3. Set preferences:
   • Mobile data → Select “Travel Data” eSIM.
   • Calls & SMS → Select MyLine/home line as default.
   • Enable “Mobile data during calls” if available.
4. Turn on Data Roaming for the travel eSIM only.
5. Test: Call someone using MyLine line, browse internet — both active.

Samsung tip: Settings → Connections → SIM card manager.
Pixel tip: Settings → Network & internet → SIMs.

Managing Calls, Texts, and Data Daily

• Incoming calls/texts: Ring/show on MyLine/home number.
• Outgoing calls: Choose line per call (dialer shows option) or set default to MyLine.
• Data usage: All apps (maps, social, streaming) use travel eSIM automatically.
• Hotspot: Share travel eSIM data with laptop/tablet.
• Switching lines: Easy in Settings — toggle data line when needed (e.g., new country).

Use WhatsApp/WeChat/Signal for free voice/video over data — no need for cellular minutes.

Troubleshooting Common Issues

• No data on travel eSIM: Check Data Roaming ON, restart phone, manually select network.
• Calls not ringing on MyLine: Ensure line enabled, Do Not Disturb off, default voice line correct.
• Battery drain: Dual active uses slightly more power — normal, not dramatic.
• SMS not received: Some banks/apps only send to primary line — set MyLine as default for messages.
• Switching countries: Turn off old eSIM data, activate new one — MyLine stays reachable.