Truphone is a free software app for your mobile phone that routes your calls over the Internet. These calls are made using VoIP using your phone’s WiFi connection and even Nokia and Blackberrys can make calls via Truphone’s network without a WiFi conn. In case you’re wondering what’s in it for Truphone, their business model is to charge lower rates than your mobile provider, particularly for international calls or calls made when you’re roaming abroad. List of supported devices. More info fr
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