The cheapest way for calling european countries on the market Make calls to Europe at unbelievable rates Calls are made over your Wifi (VOIP) connection (no airtime being used). This service does not cover calls to emergency phone numbers and should not be used as such. Call Europe is based on CSipSimple and is licensed under GNU GPL v3. More information in the app. Check the incredible rates in the application (ratess tab). Cheaper than calling cards.