I just got my Galaxy S7 and tried to find a case to print but couldn't find one so I made one. I printed this using PETG which is both and strong and flexible enough to work.
Enjoy and please post pictures of yours if you print one.
After using the new case for a few days and from your feedback I updated the design. I added slots on the back to provide better grip and let the heat out. I added grips on the side and I also enlarged and better positioned some of the holes
PowerSpec 3D Pro (Flashforge)
I set the bed temp to 80c and the filament to 240c with a 0.15mm layer height, 95% extrusion multiplier and printed at 50mm/s using a retraction of 4mm which seems to work great and provides a smoother finish.