10 Portable skin-applied sensors for measuring vital signs including body temperature, heart rate, respiration rate, and pulse oximetry; medical devices with skin-applied sensors for monitoring and analyzing skin temperature to estimate core body temperature, used with downloadable operating software for translating sensor-measured skin temperature into core body temperature; medical devices with skin-applied sensors for detecting and monitoring vital signs such as heart rate and body temperature for identifying conditions such as fever, heat exhaustion, concussions, and ovulation, intended for use with cancer patients and cardiac patients; systems for receiving, processing, and displaying data related to vital signs including temperature, heart rate, respiration rate, pulse oximetry, and movement, including cloud-based electronic medical records for storing, managing, and accessing patient data; sensors used with software for healthcare applications integrated into skin-applied devices, including algorithms for translating sensor-measured data into actionable health insights; medical devices and systems designed for detecting fever in cancer patients, monitoring heart rate in cardiac patients, identifying concussions and heat exhaustion in athletes, and tracking fertility; online platform providing a clinician dashboard for systems including skin-applied sensor devices, facilitating the monitoring and analysis of temperature, heart rate, respiration rate, pulse oximetry, and movement data collected from the sensors.