A watch includes a control member capable of managing a primary function of the watch, such as a rotating crown or a push-piece, as well as a magnetic ball that can be manually pivoted by the user about the centre thereof. A 3D magnetic sensor is arranged in the watch to detect the orientation of the magnetic field emitted by the magnetic ball, in addition to a processor for converting an electric signal generated by the magnetic sensor into an instruction for managing one or more other electronic functions of the watch. The magnetic ball is partially arranged inside the control member such that it is accessible to a user. The watch can further comprise a proximity sensor for detecting the axial position of the control member relative to the middle of the watch.