A card holder for a mobile electronic device for receiving accessory cards, which includes a substantially cuboidal housing having an open front face for inserting accessory cards, the housing including a back face, a left and a right lateral face, and a top and a bottom face, at least two guiding elements protruding from the interior side of the left and right lateral faces, respectively, and extending parallel to and between said top and said bottom face. The guiding elements define an upper slot of a first height h1 between the top face and the guiding elements and a lower slot of a second height h2 between the bottom face and the guiding elements, for receiving accessory cards of first height h1 and second height h2, respectively, and the upper and the lower slots together define a combined slot for receiving an accessory card of a third height h3.