Protecting mobile users from visual privacy attacks

An increasing number of people are using mobile devices in public places such as buses, trains, airports, coffee shops, and restaurants. Though the flexibility to work remotely using mobile devices make people more productive, this new working practice incurs un-authorized visual access of the mobile display by the bystanders, which we call visual privacy attack. Failing to prevent un-authorized people viewing sensitive information such as passwords, emails, and business information could lead to financial loss, public exposure, and embarrassment. In this paper, we propose a solution that captures the surrounding environment through user's mobile phone camera and determines whether any un-authorized person is obtaining visual access to the user's mobile screen. We develop an Android application, iAlert, that runs as a background process on a user's mobile device and alerts the user based on whether or not the displayed text on the screen is readable by bystanders.