The example is printed in one of my all-time favorite filaments, Colorfabb Grey-Blue PLA/PHA, coated in resin and polished. Get it here! (affiliate link)
A sleek, low-profile case designed for the iPhone XR by Apple. The pictured case is the "empty" version—i.e. the backing is hollow so the color of the phone can be showcased—but a "full" version is also included that doesn't have that cutout.
The case looks pretty good right off the printer, but with a little extra work I made mine look like a professionally-made finished product. Coating the print with a layer of resin before sanding and polishing removed all layer lines and gave the filament I used a nice polished-concrete look (see the close-up image).
In the files, I also included the dimensional drawings (starting on page 143 of the document) released by Apple for case/accessory designers, so that people with other versions of the iPhone can design their own cases. If you don't know how to do that yourself, send me a message and we can work something out!