Here is an interactive book on a 2D surface in 3D - the content of the pages can be interactive too! Set the radius parameter to limit the page interactivity to the corner area.
Using a stepper to control 3D objects… again… this stepper or any of the other components can be put on a 3D surface and used to control other 3D elements. This gives an alternative to a HUD or DatGui. ZIM can also do a HUD as shown here: ZIM 015 - TextureActive HUD - Code Creativity
Here we use a 2D Flipper to flip a card - perhaps an odd thing to do but if you had a card game or a memory puzzle in 3D or VR, maybe it would be easier to set it on a table or a screen. We have done several flipping games ZIM Matching Game and Secret Letters - ZIM - Code Creativity are a couple examples.