Passive RFID poses privacy risks because it can be read without user consent. On-demand RFID addresses this by requiring users to press and hold the tag to activate its antenna, using a visible dyed liquid to show connection status. A user study found On-demand RFID significantly increased trust due to its intentional and observable activation.

Smart speakers come with always-on microphones to facilitate voice-based interaction. Despite these devices' privacy features like mute buttons and their "wake-up" word detection, users struggle to trust them due to conflicting incentives. We developed Candid Mic, a battery-free, wireless microphone that can only be powered by harvesting energy from intentional user interactions. Moreover, users can visually inspect the (dis)connection between the energy harvesting module and the microphone.

Laptop webcams can be covertly activated. So, many have started covering them, but still often forget to re-attach covers. To address this problem, we developed Smart Webcam Cover (SWC): a thin film that covers the webcam (PDLC-overlay) by default until a user manually uncovers the webcam, and automatically covers the webcam when not in use. We compared SWC to manual covers and discussed trust and utility perceptions.

Virtual Reality (VR) disconnects users from their surroundings, exposing them to potential surveillance by bystanders. Solutions like live-streaming surroundings into VR inadvertently record bystanders, raising privacy concerns of bystanders. This creates a dilemma where protecting VR users' privacy infringes on bystanders' privacy. We introduce Vice VRsa, a system that alerts VR users to bystander presence and informs bystanders of VR users' monitoring status.

Improving end-users’ awareness of cybersecurity warnings (e.g., phishing and malware alerts) remains a longstanding problem in usable security. Prior work suggests two key weaknesses with existing warnings: they are primarily communicated via saturated communication channels (e.g., visual, auditory, and vibrotactile); and, they are communicated rationally, not viscerally. We designed and implemented Spidey Sense, a wristband that produces customizable squeezing sensations to alert users to urgent cybersecurity warnings.