LAUT's Pearl Series cases look three-dimensional but are totally smooth to the touch. While this case is not the most heavy-duty case you can buy, nor the slimmest, it strikes a nice balance between them resulting in a trim but protective case.
Mous is known for elegant cases made from genuine materials that pack a lot of protection into a sleek package. The Contour series is the slimmest yet, lined with protective AiroShock™ and backed with premium leather.
If you love leather but you don't like a bulky case on your iPhone, check out this slender beauty. The Ekster Smart Case has a compartment that holds a couple of cards the back, plus tiny interior compartments for a SIM card and a SIM tool.