Hey Modus,
Thanks for reaching out to us with your question!
(1) Our tickets, that are sent out to the buyers have QR codes. These can be scanned with any QR code reader app. The QR code will take you to a url that basically checks in the ticket owner.
(3) To be able to do that, the guy who is scanning the QR code needs to be logged in to the admin area of the website. The user doesn’t need to have administrative privileges, a Contributor can do that as well.
(2) Yes, 2 ticket admins can be logged in at the same time. I believe it is better if they use a different account though.
I hope this answers your questions. If you have any more, let them come, I’d be happy to answer them for you.
Cheers,
Andras