IMPORTANT NOTE!
Slicer has a small problem with the Print In Place part. Simple fix for this is to change the ‘Slice Gap Closing Radius’ from 0.049mm to 0.010mm. Profiles are updated with this setting!

 Setting the print in place part to 100% infill and 3 wall loops will help with strength.

Made a adjustable book stand/display with a design at the request of a friend, also made a phone variant for this.
Had a lot of fun designing a print-in-place mechanism for it to lock in place.

Both the book stand and phone stand use HolderConnector, HolderStand and LockingMechanismPrintInPlace.
For the book stand also print HolderDesign and HolderFrame.
While for the phone stand print PHONEHolderDesign and PHONEHolderFrame.

Assembly:

The assembly for this item is straight forward, but it might be a tight fit.
After printing all parts I suggest you to carefully break the locking piece free by holding the cylinder part in one hand while turning the knob with the other. By carefully turning the knob a little arm should come out (Don't turn it too much when outside of the stand, it will break), this is the part that keeps everything in place. Fold it back in before pressing the lock in place when told so in the instructions, step 3.

1. Put the HolderConnector in the HolderFrame, keep in mind that the HolderConnector' has a wider part and a smaller part.
2. Click the design in place in the Connector+Frame, this should lock the Connector in place.
3. Place the assembly in the stand and press the locking mechanism in place. (This is a really tight fit, might need a little sanding if this does not fit)
4. Enjoy your book or phone stand!

Creating your own design:
You can easily create your own design in your favourite CAD software. The dimensions for the HolderDesign (Book stand) are 142mm x 92mm x 3.5mm and the dimensions for the PHONEHolderDesign (Phone stand) are 142mm x 67mm x 3.5mm.