Tripod mount cellphone holder

This holds a cellphone in a 42mm tripod mount shoe. In this case it's an HTC One though the SCAD file is parametric and I've adjusted it to a Huawei P20 Pro with no problem.

It is also possible to warm the arm up with a blowtorch, hot air gun etc. and kink it to fit your phone. Probably best to take the phone out first!

Video showing a view around the phone holder in a tripod is at 1:35 here: https://youtu.be/riJ47nAv7Bs

Or, as is shown later in the video, you can just leave off the grip (module phone_grip() in the OpenSCAD file) and use it as a base to stick a self-adhesive GoPro mount on.