If the speed is over 64 kbps, there will be no problem for voice calls.
However if it is under 64 kbps, the performance can be deteriorated.
Note: As for video calling, we recommend that you use Wi-Fi.
[Maintenance Notice]
We will have a server maintenance during the following time. The SkyPhone service will be available, but the maintenance might cause instability in the service during the time.
We are very sorry for any inconvenience this may cause you and appreciate your understanding.
Maintenance Period: Tuesday, June 23, 2026, 9:00 am – 12:00 noon (JST)