Sensitive information is increasingly moving online and as data moves further from the control of its owner, there are increased opportunities for it to fall into malicious hands. The Web is comprised of three untrusted components where there is a risk of information compromise: networks, service providers, and clients. This thesis presents Trusted Mobile Overlays: a system that leverages trusted mobile devices to protect users from these untrusted components of the Web, while minimizing deployment difficulties. It presents a high-level design of the system as well as a prototype that implements the design.