Abstract: A wearable computing device includes a housing having a wrist-side face configured to sit against a wrist of a user of the wearable computing device when being worn by the user, an electronic display arranged within the housing, a plurality of biometric sensor electrodes positioned on the wrist-side face so as to maintain skin contact with the user when being worn on the wrist by the user, and at least one driver communicatively coupled to the plurality of biometric sensor electrodes. Each of the plurality of biometric sensor electrodes continuously measures, at least, one or more parameters indicative of electrical impedance of the user at a location of the skin contact.