A portable electronic device comprising: a first housing comprising a display, a first end, a first mating end and a first rear surface opposite the display; a second housing comprising a second end,a second mating end and a second rear surface; a hinge assembly coupling the first mating end of the first housing to the second mating end of the second housing, the hinge assembly comprising: a pair of pinions (402, 406 / 410, 414), an inner one of the pair of pinions (406, 410) being coupled to the first housing and a first pinion body of the inner one of the pair of pinions (406, 410) projecting from the first rear surface of the first housing to engage an inner rack (408,416) coupled to the second housing, an outer one of the pair of pinions (402, 414) being coupled to the second housing and a second pinion body of the outer one of the pair of pinions (402, 414) projecting from the second rear surface of the second housing to engage an outer rack (404,412) coupled to the first housing, and an axle extending through apertures of the first pinion body and the second pinion body and supported by the pair of pinions (402, 406), the second housing being movable relative to the first housing from an open position in which the axle is in a first position near to the first mating end and the second mating end and a folded position in which the first rear surface of the first housing is facing the second rear surface of the second housing and the axle is in a second position spaced from the first mating end and the second mating end and spaced between the first housing and the second housing such that the first mating end and the second mating end are movable toward one another to move the portable electronic device to a partially open position for clipping to an object; and a processor in electrical communication with electrical components in one of the first housing and the second housing. a first housing comprising a display, a first end, a first mating end and a first rear surface opposite the display; a second housing comprising a second end,a second mating end and a second rear surface; a hinge assembly coupling the first mating end of the first housing to the second mating end of the second housing, the hinge assembly comprising: a pair of pinions (402, 406 / 410, 414), an inner one of the pair of pinions (406, 410) being coupled to the first housing and a first pinion body of the inner one of the pair of pinions (406, 410) projecting from the first rear surface of the first housing to engage an inner rack (408,416) coupled to the second housing, an outer one of the pair of pinions (402, 414) being coupled to the second housing and a second pinion body of the outer one of the pair of pinions (402, 414) projecting from the second rear surface of the second housing to engage an outer rack (404,412) coupled to the first housing, and an axle extending through apertures of the first pinion body and the second pinion body and supported by the pair of pinions (402, 406), the second housing being movable relative to the first housing from an open position in which the axle is in a first position near to the first mating end and the second mating end and a folded position in which the first rear surface of the first housing is facing the second rear surface of the second housing and the axle is in a second position spaced from the first mating end and the second mating end and spaced between the first housing and the second housing such that the first mating end and the second mating end are movable toward one another to move the portable electronic device to a partially open position for clipping to an object; and a processor in electrical communication with electrical components in one of the first housing and the second housing.