This guide describes settings that must be configured on iPhone and iPad for use overseas and how to use these devices.
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Check your subscription status and apply by clicking the button below.
Turn your device's international settings on [1]
(1) Making calls and using SMS and data communication
(iOS 13)
"設定(Settings)" → "モバイルデータ通信(Cellular)" → "通信のオプション(Cellular Data Options)" → "データローミング(Data Roaming)" to ON
<If necessary>Airplane Mode setting
If necessary, set your device to Airplane Mode during your flight.
(2) Making calls and using SMS only
(iOS 13)
"設定(Settings)" → "モバイルデータ通信(Cellular)" → "通信のオプション(Cellular Data Options)" → "データローミング(Data Roaming)" to OFF
From the settings, check that "Data Roaming" is set to on.
Once you have arrived abroad, you be notified via SMS of whether or not you can use the World Data Flat service. This SMS notification is sent free of charge.
By clicking the URL in the SMS notification (http://www.sekai.kddi.com/kddijp-up/), your browser is launched and the "start service" screen is displayed. If using the World Data Flat App, the "start service" screen is displayed by starting the app.
Turn Wi-Fi off to display the "start services" screen.
Push the "start services" button
Turn Wi-Fi off to display the "start services" screen.
For World Data Flat
You should now be able to use.
If you tap "Enable 4G" from "設定(Settings)" → "モバイルデータ通信(Cellular)" → "通信のオプション(Cellular Data Options)" and switch from "音声とデータ(Voice & Data)" to "データ通信のみ(Data Only)" or "オフ(Off)" while using your iPhone (iOS 8.3 or later) overseas, [2] after returning to Japan and restoring the settings to what they were before you went abroad, reconfigure the settings for voice call services such as Answering Service EX and Call Forwarding Service.
for how to set (choose a voice call service)