I really like gears - you can see it on my models, there are many on this topic. I was inspired by similar holders, but I added new things to this one - it can be printed print-in-place, I added a locking wheel so that the gears do not move under load.
The Print-in-place version of the model cannot be disassembled.
During the first tests, I found that the first one could be disassembled, so I added separate parts if you wanted to have a holder in different colors.

26.2.  Update !!   Added number of cutouts in the locking cylinder for finer adjustment of the holder angle. From 4 to 8 cutouts. 

If there is a problem with releasing the Aretation part, turn the knob a little sideways or tap on the hexagon. The tolerance between the parts should allow separation without problems. Try downloading the model again, I uploaded looser parts

Optional model with fine angle locking added - entire Print-in-place holder, also individual parts  - with 12 locking cutouts

24.3. UPDATE !!!

Added after comments, the part of the Gear Holder arch that holds the phone has a cutout for better control of the phone,files are in the Gear Holder with Cut-out directory

I make all my models for you for free, but if you would like to support me, you can become a member of my club!