Abstract: Carrier system for a mobile device positionable in various directions in space, such as a directive light source, including a trolley which can move along a guide ramp. The ramp includes two helical rails turning about a given longitudinal axis, and the trolley includes a pair of axles with parallel axes holding the ramp therebetween. Each axle is provided with a central body engaging with an associated face of the ramp by wheels capable of running the ramp and guiding the axles when the wheels move along the ramp, with which the wheels are held in contact by an elastic connecting member pulling them towards each other. The light source is fixed to the central body of one axle, and the central body is coupled in rotation with the wheels of the axle.