Getting StartedUpdated: January 10, 20262 min read

What is an eSIM and How Does It Work?

New to eSIM? Learn how this digital SIM technology makes international travel cheaper, easier, and eco-friendly.

An eSIM (embedded SIM) is a virtual SIM card that is built directly into your phone's hardware.

Unlike the traditional plastic cards you have to swap in and out with a tiny needle, an eSIM is a digital profile that you can download over WiFi. It does everything a physical SIM does—connects you to 4G/5G networks—but without the physical hassle.


🛠️ How It Works: A Simple Analogy

Think of it like streaming music vs. buying a CD.

  • Physical SIM (The CD): You have to go to a store, buy the physical object, put it in your player (phone), and carry it around.
  • eSIM (Streaming): You buy it online, download it instantly, and it plays immediately.

With Roamiya, you scan a QR code, and "poof" — a new local data plan appears on your phone, ready to use in Japan, Europe, or the USA.


✈️ Why Travelers Love eSIM

1. Zero Shipping, Zero Waiting

Forgot to buy a SIM card? No problem. You can buy a Roamiya eSIM while waiting at the airport gate. It arrives in your email in seconds.

2. Keep Your Home Number Active

eSIM allows for Dual SIM functionality.

  • SIM 1 (Home): Keep your physical SIM inside to receive SMS verification codes (OTPs) and emergency calls from home.
  • SIM 2 (Travel): Use the Roamiya eSIM for all your mobile data (maps, Instagram, browsing).

3. Better Prices

Local roaming with your home carrier (e.g., AT&T, Verizon) can cost $10/day. Roamiya plans often cost that much for an entire week.

4. Eco-Friendly

No plastic manufacturing, no packaging, no shipping trucks. It's the greenest way to connect.


📱 Will It Work on My Phone?

Most iPhones since 2018 (iPhone XS and newer) and most standard Android flagships (Samsung S20+, Pixel 4+) support eSIM.

👉 Check our full Compatibility List here


🔄 Switching Between SIMs

When you install a travel eSIM, you don't lose your main number. Your phone settings will let you choose:

  • Default Voice Line: Primary (Home)
  • Mobile Data: Roamiya (Travel)

This setup ensures you stop paying expensive roaming data fees while staying reachable.


Ready to Roam?

Browse our data plans for 150+ countries and regions. Connection is just a QR scan away.

👉 Shop eSIM Plans

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