You can call from a computer or mobile device. Calls use approximately 0.2 MB of data per minute. Whether on a computer or mobile device, you can’t use incoming call options. These options include call recording or call transfer. And, if you use a Bluetooth® device, you might not be able to use the buttons on it to answer calls or hang up.
To use Google Voice to make calls through your mobile carrier, link your mobile number. The amount of data you use depends on your carrier’s network quality and speed.