An amazing amount of new technologies has been introduced into our homes in the 21st century. Among them, are the widely-used smart devices, such as smartphones and smart TVs. These smart devices are known to gather data, which raises concerns about privacy and the risk of information leakage. The purpose of this book is to bring to light the dangerous practices used by software in such devices that lead to the leakage of sensitive data; and propose a system that identifies the sources of the leaks. As connectivity is the main feature of smart devices, the system investigate their network traffic, in search of design vulnerabilities. More than just passive search, the system also performs a Man in the Middle attack in order to decrypt and analyze the information transiting through the encrypted traffic. Experimental results demonstrate that widely-used applications such as PayPal present several sources of leakage. The system allows users to assess the risks of utilizing a smart device or any of its applications. It can also be used by companies as a means of auditing the network traffic of their product in order to verify its quality in term of privacy and risk of leakage.