Hi Harisk,
I realize that this is +1 year old post and I'm not sure whether you found the answer you were searching for, but I will post the answer anyway.
Quantum Hall Effect is an exciting topic with a bunch of weird phenomenons.
Von Klitzing constant or Hall Resistance at a filling factor=1 is considered one of the most important factors (if not the most), it is discovered that it is quantized with extremely high precision (1 in billionth) at a specific energy state (Landau Level) due to high magnetic field. Hall Resistance can be used to find hall mobility thus material conductance mobility and find carrier type and density.