180 Degree Fisheye Lens Super popular accessory for mobile cameras.
The ProMaster Mobile Lens System features a dual mounting system engineered to provide photographers maximum flexibility in how they attach each lens or filter.
Mounting Method 1: A small thin ring, with adhesive backing, is applied to the mobile device or case, so the lens can cling magnetically. Mounting Method 2: The lens can be screwed into a small, hinged clip mount that looks like a clothespin. Open its jaw and position over the lens of the mobile device.