Ultra-Low-Power Mode for Screenless Mobile Interaction

Smartphones are now a central technology in the daily lives of billions, but it relies on its battery to perform. Battery optimization is thereby a crucial design constraint in any mobile OS and device. However, even with new low-power methods, the ever-growing touchscreen remains the most power-hungry component. We propose an Ultra-Low-Power Mode (ULPM) for mobile devices that allows for touch interaction without visual feedback and exhibits significant power savings of up to 60\% while allowing to complete interactive tasks. We demonstrate the effectiveness of the screenless ULPM in text-entry tasks, camera usage, and listening to videos, showing only a small decrease in usability for typical users.