This was designed to fit the the devices I need so should be relatively universal. Tested with sony xperia mini pro, logitech harmony smart remote, Humax DR002 and JVC RM-C3231. You should be able to scale it to fit other devices. It is the one on the left in the pics. The next one over is a print from thingiverse but I started from scratch.

The back is flat to allow mounting using 3m command strips.

The orientation is intentional, for some reason I get less issues with lifting corners if the long side is running front to back on the bed.

The open design is to make it quicker to print and use less PLA.

I printed with 10% infill and 3 shells.