The locking system will use NFC? for access. The private foyer on the first floor will lead to the elevator where the tenant can select their floor. The same key can be used to unlock their unit, and make sure they can gain entry. There will also be a PIN pad at the doors which will also allow the tenant inside. The tenant can elect to have their PIN pad removed from their unit, but they will have a hard time getting things resolved if they lost their phone, and their phone is the key. The PIN pad is a hole in security, but there will be a camera in the public hallway to catch any would be bad actors.
The locking system will support Apple Home, and Google Home systems. This will allow you to use your handheld as the key, and give you access to your apartment. In all of my time of having a cellular phone, I only lost it one time. Since I had a cellular phone since 1991, I will say that is a good track record. I don’t see most people “forgetting” something so integral in their daily lives.