Apple has filed for a patent (number 9,699,546) for “earbuds with biometric sensing” that hints at future AirPods with enhanced capabilities. The invention involves earbuds configured with one or more biometric sensors.

At least one of the biometric sensors is configured to be pressed up against a portion of the tragus (prominence on the inner side of the external ear, in front of and partly closing the passage to the organs of hearing) for making biometric measurements.

The housing of the earbud can be symmetric so that the earbud can be worn interchangeably in either a left or a right ear of a user. In such an embodiment, the earbud can include a sensor and circuitry configured to determine and alter operation of the earbud in accordance to which ear the earbud is determined to be positioned within.