Props to you, Philippe, and the rest of the team - you’ve done a fantastic job taking questions / feedback from the community on board and adjusting. The difficulty of explaining something so complex and foreign to much of the user base cannot be overstated. This is an excellent effort.
When you say “we actually use its size on screen to determine this [LOD] since we want those details to appear when zooming as well”, I’d assume that the sizes are different for different devices? For example, 4 inches on an iPhone 6 is nearly the entire screen, while it is only about 1/3 of the screen of an iPad Pro.
Interesting question… I’d think you could use an absolute size given mobile devices of all sizes tend to be used in a way that results in the screen being the same distance away from the eyes, and tablets (and other larger screen devices) typically have more resources to work with. I’m by no means an expert and could be totally wrong though.