Dont waste your money on this app like I did. No matter how hard youll try to reach the developer for support, dont be shocked if you get no response. This app hardly works with iPhone 5, and not at all with 4S. It will not receive incoming calls. The developer misleads when he mentions it does. Not many settings to manipulate either. Its slow and crashes every time its used. The quality of voice is terrible when you get it working the odd time. SAVE YOUR MONEY is my message to you.
ALIHK about iGVoice - Google Voice™ VOIP Phone Call + SMS, v1.6