The negative thing is the QR Code Key.

You can only enter the building via QR Code on your phone. Unfortunately one day it was not working. And another day, our next-door neighbor was waiting outside the building when we reached the entrance at 10 pm.

When he saw us he screamed like a happy child because his phone run out of charge and he could not get into the building.
QR Code Key is nonsense. Please give people a normal key.