Apple's iPhone designs are notoriously fragile, so even though they're a pleasure to use naked, most choose to put them in a case. If you're going to do so, you might as well choose one that goes beyond simple protection. Bitplay's Wander Case has a multi-use carabiner that doubles as a stand, enabling attachment to a variety of clothing, straps, and other accessories. It also comes with a removable adhesive pad, has an interchangeable backplate, and provides shock protection with a TPU & silicone build.
Dimensions: 5.51" x 2.83" x 0.69" (iPhone 12 mini), 6.10" x 3.11" x 0.65" (iPhone 12/12 Pro / Weight: 1.87 oz (mini), 2.12 oz (12/Pro)