Your travel companion
About Mobile Companion
Mobile Companion gives travellers to Japan mobile data on the NTT docomo network, with an app to keep an eye on it and top up mid-trip. Behind it is Japan Companion 合同会社, a company based in Tokyo.
Who we are
Mobile Companion is a brand of Japan Companion 合同会社 (Japan Companion GK), a Japanese company based in Tokyo. It sells the eSIMs on this website and publishes the Mobile Companion app on the App Store and Google Play.
What we do fits in one sentence: getting you online in Japan as soon as you land, without hunting for WiFi or queuing at a shop.
What we do
Data eSIMs for Japan on the NTT docomo network, in 5G where your phone supports it: mobile data only, with no Japanese number for calls or texts.
- Installed in 1 minuteFrom the app or with your QR code, at home before you fly.
- Online as soon as you landIt connects to the Japanese network by itself, with a real Japanese IP address.
- Starts at your first connectionYour plan begins when you first connect in Japan, not on the day you buy it.
- Hotspot allowedShare your data with your laptop, your tablet or a friend’s phone.
You buy your eSIM on this website or in the app, and top up from the app or your account if your data runs low. Your usual SIM stays in place, so your UK number can stay active for calls and texts if your UK network allows it.
The app
The Mobile Companion app, published by Japan Companion LLC (the name on its store listings), is on the App Store and Google Play, in English and French.
- It checks that your phone is eSIM-compatible before you buy.
- It helps you install your eSIM, QR code included.
- It tracks your data and lets you top up during your trip.
- You log in with the same account as on the website.
Download the Mobile Companion app
On iPhone and Android, in English and French, with the same account as on the website.
Scan it with your phone
Screenshots, features and compatibility: it’s all on the Mobile Companion app page.
How we help
On WhatsApp, a real person replies 24/7, in English or French, before and during your trip. You can also write to contact@mobile-companion.com: every way to reach us is on the contact page.