How much data does a voice call use?

[davidtheprof]

you see different estimates,
e.g. https://support.skype.com/en/faq/FA1...y-mobile-phone
Skype claims about 1MB/min if calling a land/mobile number, 3MB if Skype to skype (on voice).
Other sites claim around 0.7MB/min.
so yes, this is often best with cheap data.