Groove IP by snrb Labs brings mobile VoIP to the Android market. Voice without minutes is exactly what it means when you use this app in conjunction with Google Voice. You can make unlimited calls to any phones in the U.S. and Canada by using the data connection of your mobile device without using any of your mobile minutes. This mobile VoIP app supports making and receiving calls using Wi-Fi and/or 3G/4G data connections.
With Groove IP, your Google Voice number travels with you even overseas. So when traveling overseas, you can make and receive calls as long as you have Wi-Fi connection. This alone is worth the $4.99. You can get it at (Google Play). Set up was simple. All you had to do was install the app and then enter in your Google Voice username and password.
Note: Calling international numbers still incur international rate charges.
You must have Google Chat as a “Forwards to” number in your Google Voice account. See screenshot below.