How many VOIP minutes?
Does anyone know how many minutes one could talk with 500MB of data? Is that about 100 - 150 minutes a month (depending on rounding.)
GrooveIp claims 1.2 MB/min = 400 mins/500 MB.
I was thinking a VOIP codec might require somewhere between 30 - 75Kbps. I had Vonage for a number of years a long time ago and I thought they offered a couple different stream rates...these numbers stick in my head for some reason.
So I considered something in the middle around 50Kbps which would be about ~150 minutes.
Of course I didn't consider that these bit rates would probably deliver land-line or better quality -- which would far exceed typical cell phone sound quality. If we lower the bar to cell quality, it's probably realistic to get a lot more minutes as you cite.