Intersection point

== Touch the two edges you want to intersect (or find the minimum distance), with the little blue pointer, maintaning the Trigger Button pressed. This will create a vertice on the first edge, which is closest to the second. ==

Touch two edges a, b with a common vertice, and then a third one c, to get the intersection of the line c with the plane generated by a and b.
Touch 4 edges forming two planes, to find two points in the intersection line.