The present invention is directed to a wearable system wherein elements of the system, including various sensors adapted to detect biometric and other data and/or to deliver drugs, are positioned proximal to, on or in the ear canal of a person. In embodiments of the invention, elements of the system, including drug delivery devices, are positioned on or in the ear canal for extended periods of time. For example, an element of the system may be positioned on the tympanic membrane of a user and left there overnight, for multiple days, months, or years. Because of the position and longevity of the system elements in the ear canal, the present invention has many advantages over prior wearable biometric and drug delivery devices.