I've never worked at a place that didn't have RFID tags that opened the doors. This is old old tech and doesn't require a smartphone at all. One place I worked

I've never worked at a place that didn't have RFID tags that opened the doors. This is old old tech and doesn't require a smartphone at all. One place I worked you needed special permission to be there after core hours so your RFID tag didn't open the door unless you got permission from security then they enabled your RFID tag. Another place you had to sign in after hours so all RFID tags didn't work after hours and you had to go in the front door through security. Badges are still not antiquated, they convey other information once you are in the door.