We created 3D-printable files for a Rev Robotics level shifter case and phone holder. These are designed for the Motorola E4 phones with the cases from FIRST. The cable holders are used to protect the USB and cable connections and prevent them from disconnecting.

The STL files can be found here:
https://drive.google.com/open?id=1nfZRQu1fM45pRrUwfNMc5jGhKpN8irZ7