Offices use RFID key fobs with local, dedicated hardware. An internet connected mobile phone based entry system is too complex, and will have particular difficulty integrating into the existing supply/service chain for these kind of systems.
We really, really don't need mobile phone based key unlock systems. I een considered building one for our home, but diacarded the idea due to the user experience complexity of having to use my phone instead of a simple key (but still carrying a key in case of failure).
As for Airbnb users, all you need is a programmable keypad (or an RFID entry system.)
I' m remarkably negative because it's a bad idea. I'm not going to pretend to like the idea to spare someones feelings. To my uninformed judgement, it's something that will not work.
There are numerous problems with the market, that IMHO, Lockitron is attacking (which is not the residential market)
Why wouldn't ever office to lease use this over elaborate and expensive key entry systems?