Traditional Culture Encyclopedia - Hotel reservation - What should I open to travel abroad to make foreign calls cheaper?

What should I open to travel abroad to make foreign calls cheaper?

If you want to use China card abroad, you can open international roaming, but the cost is more expensive.

You can also use VoIP. Such as carefree travel, ali tong, etc. You can make free overseas voice calls and preferential internet traffic. I use the worry-free voice call function, which is stable and will give free call duration.