I just got a Google Voice number and had a few questions to ask the experts among you: 1. I understand that it's possible to make free phone calls (meaning, I don't use my anytime minutes) from my Android cell phone using Google Voice and a wifi connection. I also believe that it's necessary to download an app in order to do this (for example, GV Dialer, GV Mobile, GV Callback, etc). Is it necessary to download one of these apps to make free phone calls, or am I mistaken and I can just do this using the Google Voice app? If it's necessary, which app do you think is best? If it's not necessary, what's the advantage of downloading these apps? 2. What's the difference between making free phone calls using wifi and Google Voice versus using, say, Fring or any similar apps out there (other than the additional functionalities of Google Voice, such as call forwarding, etc)? Are there advantages to one over the other? 3. This may sound like a naive question but does this technology (free phone calls using wifi) work while driving or must I remain in one location with a wifi connection? 4. I text and call overseas. Are there ways to text and/or call overseas for free using any of the above mentioned apps? Thanks for your help!!