Ensuring Users' Privacy and Security on Mobile Devices

Mobile devices have become increasingly powerful and popular. The number of mobile users is growing fast and people use their phone nowadays for a plethora of things (e.g., e-commerce, mobilebanking, e-mail, social, etc). While powerful mobile devices are more convenient for users, the volume and sensitivity of information they contain are crucial to a user's privacy as well as her security. Sometimes the latter is taken for granted (wrongly). In this dissertation, we propose three major frameworks to protect users' privacy and security on such mobile and highly capable platforms. The three frameworksare as follows. VideoDroid, an Android framework that allows users to conduct video calls on open Wi-Fi networks while preserving their privacy and minimizing the performance penalties. Droid M+, an Android framework that helps developers transform their legacy apps to apps that support the newer revocable permission model that was introduced by Google to help users' privacy. RootExplorer, a fully automated system that is able to detect malware carrying root exploits by leveraging root exploits from commercial one-click root apps to learn the exploits’ behaviors and their expected environment