With recent multiplication of cloud telecom provider like Twilio, Plivo, Tropo, Nexmo, TelAPI, Apifon…. and many more popping out every day, I had this idea about how easy it should be now to build a calling card solution based completely in the cloud and on one of the provider’s rich API. A weekend or so of coding, thought I and it should be ready for production! But little did I know about what it takes to create something as simple as a calling card service.