An apparatus for detecting physiological or contextual information includes a flexible section(s), a housing removably attached thereto, one or more sensors and a processor. The apparatus may have adjustable operating parameters. An alternate apparatus measures heat flux and includes a housing, a known resistivity base member, a processing unit and two temperature measuring devices, one in thermal communication with the body and the other in thermal communication with the ambient environment. Another alternate apparatus includes a housing having an adhesive on a surface thereof for attaching the housing to the body. A further alternate apparatus includes a housing having an inner surface having perpendicular concave and convex shapes. An apparatus for detecting heart parameters includes an acoustic-based non-ECG heart parameter sensor and a filtering sensor(s) for generating a filtering signal related to the non-heart related motion of the body.
