TherMobile: Measuring Body Temperature Using a Mobile Device

The spread of COVID-19 issues high demand on measuring body temperature, which necessitates thermometers. To alleviate a burden to equip/carry thermometers, this paper develops a framework 'Ther- Mobile' that measures body temperature using a commercial-off-the-shelf smartphone that most people carry everywhere. Considering that most (if not all) smartphones have a temperature sensor on its battery, we utilize heat transfer from a body part that makes contact with the smartphone, to the smartphone battery. To this end, we collect a time series of the smartphone battery temperature for different pairs of the initial temperature of the smartphone battery and the temperature of a body part, and then classify them. To enable the data collection and classification to infer the temperature of the body part, we address important practical issues, including how to gather data for different target temperatures of a body part (although human body temperature is not controllable), and how to minimize a burden for individual users to gather all necessary data. Our experiments demonstrate that 'Ther- Mobile' achieves 90.0% accuracy of measuring body temperature with 1.0°C granularity, enabling a commercial-off-the-shelf smartphone to substitute for a thermometer without any additional hardware.