This project was inspired by 0xyJin's living hinge phone stand: https://www.instructables.com/id/Phone-Stand-Headph... My goal in this project was to create a similar, but smaller and simpler, design that could fit on a keychain (hence the hole at the top).
My final design, after about 10 revisions, is a living hinge that can bend back to prop the smart phone up (when it's horizontal, that is. It doesn't work properly if the phone is vertical.) The red sections in the picture above are rasterized to act as a trough to keep the phone from sliding off the stand. There is a 1/4 inch hole at the top of the holder so it can be threaded onto a keychain. The overall dimensions of the holder are 2 inches by 1.5 inches by 0.115 inches.
I laser cut the part out of 0.115 inch craft wood using 100% power and 2% speed for the black lines and 100% power and 35% speed for the red. Then I used sandpaper to remove the creosote from the finished part.
One of the main problems with this design, however, is that if the smart phone is left on the holder for an extended period of time, the living hinge will keep its bend shape and will have to be bent in the opposite way to be level with the rest of the part.