App is acceptable, system is terrible
The app is not difficult to use; just know you need to have all of the passports and all the people who want keys to be physically present for photographs by the app before beginning. The associated hardware, however, is beyond terrible, making the system as a whole frustrating. Both the building and apartment locks worked the first day. On the second day it locked us out of the apartment on a 105° day. The owner tried to override it remotely, but it would not respond to him either, although the app incorrectly claimed it was open. We were left standing in the sun until the owner could dispatch someone to drive over and physically let us in with a real key. He gave us physical keys to use after that. I am an engineer (Ph.D. from MIT), and the quality of one of the two locking systems we used was of laughable quality. Surprisingly, it was the better-constructed software lock that failed to work. Perhaps it failed because of the hot weather. Regardless, the expensive system failed, and the lack of helpful feedback from the app (“Opened!” when in fact locked) does not help. I will avoid using any Airbnb’s that requires this app in the future.