GSR measurement detects human skin impedance under different situations. A variety of events affect the skin impedance of a human body, such as changes with the ambient environment, stress from a sudden event, and sweating from physical exercises. GSR devices can be used in medical treatment, lie detection, and wellness monitoring. The MAXREFDES73# reference design is a wrist-worn GSR measurement device that monitors both skin impedance and temperature on a user’s wrist. With a mobile device for Android, a user can monitor his or her skin resistance and temperature within 20 m through the Bluetooth low-energy (BLE) wireless interface.