So let's get started by first setting up our scene and then I will show you how basic navigation works. To define the unit system you would like to work with with your finger tap on the lower right corner icon.
Tap on units and with your finger you can scroll up and down and then select the unit system you would like to work with. I by default always work with millimeter.
You can actually see on the upper right corner on the screen, there's a small grid icon and to the right it's written 0.5 millimeters, and that actually means that the small squares of the grid are actually scale-wise representing 0.5 millimeters.
And based on your zoom level that actually will adjust. To change the views with your finger you can tap on the 3D widget icon in the upper right corner and then select from the different camera positions like: top, bottom, front etc.
There's also kind of like an option for the grid. For ghosting so you can see hidden edges, as well as a reset camera button.