The loss of control over a new-generation mobile device (e.g. loss of device or short time of inattention) can have negative impacts on the owner's privacy due to the increasing number of privacy-sensitive data stored on such devices. Current mobile platforms either lack the required protection mechanisms or the implementations lack a balance between the level of security and usability. In order to fill this gap, we propose a design for a local security mechanism for mobile devices by using an reasonable combination of existing technologies.