The invention provides a monitoring device suitable for attachment to a surface of a subject, the device comprising a data collector and a processor. The data collector comprises a flexible foil attached to a less flexible socket, where the foil forms a dermal side surface of the data collector for adhesion to a skin surface of a subject to be monitored. To enable communication of electrical signals between the data collector and the processor, the data collector comprises a distribution structure formed as a pattern of an electrically conductive material on an outer surface of a foldable sheet. The foldable sheet forms a layer in the flexible foil and comprising an interface portion which is folded into an aperture in the socket to form a coupling inside the cavity for electrical communication with a matching coupling of the processor when the processor is received in the cavity.
