Embodiments of the present disclosure provide techniques and configurations for an apparatus for opportunistic measurements of a users physiological context. In one instance, an apparatus may comprise a hand-held device, and include a surface that includes two or more electrodes disposed on the surface to contact with portions of the users hands when the hands are in contact with the surface while the user holds the hand-held device, to obtain signals to be used to determine a physiological context of the user. The device may further include circuitry coupled with the two or more electrodes to identify at least two of the electrodes that are in contact with the users respective portions of hands and, on identification, collect the signals to determine the physiological context using the identified electrodes while the contact between the portions of the hands and the identified electrodes is maintained. Other embodiments may be described and/or claimed.
