You can download it here
Iphone:
https://itunes.apple.com/se/app/confetti-check-in/id1440794747?mt=8
Android:
https://play.google.com/store/apps/details?id=events.confetti.confetti
With the app you can have multiple people doing the check in from different entrances and still keep track of who is in and who is still on their way.