This adjustable-angle phone holder securely holds a smartphone in either portrait or landscape mode. To use landscape mode, simply turn the holder upside down, so the USB-C jack doesn't get in the way.

A USB-C right angle adaptor slides into the holder, so that a USB-C jack sticks upwards for the phone to slot in (in portrait mode). Charging can then be done while the phone in being used by plugging in a USB-C cable into the side the holder. If the adaptor is a loose fit, then a few drops of superglue (or adding a layer of tape) will secure it. If you have an older phone with a microUSB socket instead, then there are suitable right-angle adaptors on eBay/AliExpress, but you'll probably need to adjust the model to match the exact adaptor.

A thin metal plate can be slotted into the base as ballast, which really helps stabilise the stand when a phone is placed on it. Just set the slicer to pause the printer at the correct layer, slot in the metal plate, then continue the print. Any dense metal (not aluminium) can be used: I used 2mm stainless steel. Before printing, measure the plate and adjust the model so it fits well. The “100×50mm” plate I bought was actually 91.2×45.5mm.

4× Silicone feet are stuck on the bottom, so the base has more grip on work surfaces. You don't want it sliding around the desk when you are trying to swipe right! A really soft TPU/TPE filament could probably be used instead, but self-adhesive silicone rubber feet work well and are very cheap.

Parametric design

A parametric design file for FreeCAD is included, allowing for quick changes to the dimensions, for example the pocket for the metal plate or the indents for the silicone feet. See the included spreadsheet ‘Params’.

This original work was built from scratch, but partly inspired by Devin Gentner's 2017 design https://www.myminifactory.com/object/3d-print-gear-phone-holder-43403, plus the “euro” idea from https://www.thingiverse.com/thing:4982411/files