Hosts
Add each host, then print or share their ticket. Everyone that host invites carries this same code to the door.
Backup
Everything is stored only on this device/browser. Use export to move your hosts and history to another device, or as a safety copy.
Door
Start a session, then point the camera at each invitee's code. One scan counts one guest to their host. The count keeps saving as you go — closing or minimizing the page won't reset it.