I printed out the design by na427, but the lip was obstructing the cell phone's screen. I liked the design otherwise, so I decided to remix it.

The design has been made from scratch using SolidWorks 2013, following roughly the dimensions and design of the original stand. I also made the angle of the phone a few degrees less steep, and added fillets to the bottom corners to prevent warping.

It have tested the design with Nexus 5, Nexus 4, Galaxy Nexus and Galaxy S4. Most modern smartphones will work great with it, both in landscape and portrait positions.

Tip: Scale it a bit wider to make a great stand for bigger tablets! The original dimensions are good for slim 7" tablets, such as the Nexus 7.