Raising User Awareness about Privacy Threats in Participatory Sensing Applications through Graphical Warnings

Mobile phones are increasingly leveraged as sensor platforms to collect information about user's context. The collected sensor readings can however reveal personal and sensitive information about the users and hence put their privacy at stake. In prior work, we have proposed different user interfaces allowing users to select the degree of granularity at which the sensor readings are shared in order to protect their privacy. In this paper, we aim at further increasing user awareness about potential privacy risks and investigate the introduction of picture-based warnings based on their current privacy settings. Depending on their privacy conception and the proposed warnings, users can then adapt their settings or leave them unchanged. We evaluate the picture-based warnings by conducting a user study involving 30 participants. The results show that more than 70% of the participants would change their settings after having seen the picture-based warnings.