Cellbris UniVoIP (GSM to VoIP and VoIP to GSM gateway ) is a remote extension, connecting cellular phone directly to VoIP. By utilizing VPN (very cheap or free calls from one SIM card to another) user can place calls via VoIP

Here is a sample how it works with VoIP:

With UniVoIP you dont need any VoIP adapters, it connects directly to your internet connection.
If you already have VoIP adapter you might want to check our remote GSM gateway that connects directly to your Voice over Internet adapter and gives you same possibilities as our UniVoIP gateway

Now you can place international calls from your mobile paying few cents.