There are two different kinds of check-in.

Realm offers two different varieties of check-in.

Group check-in is used to secure kids' events like Sunday morning classes, VBS classes, nurseries, and so on. It can track attendance, but its primary goal is to make sure that only authorized parents or guardians pick up their children.
Use a group kiosk for things like a children's Sunday school class or party. For adult venues, like concerts with registered attendees, use a registration kiosk.

Registration check-in is used for adult gatherings like concerts and seminars. Its goal is not security, but taking attendance, collecting information on new attendees, and so on. It also helps make sure that, when appropriate, only registered guests attend events.
Use a registration kiosk for things like a concert, where you've registered attendees ahead of time. For monitored events like a children's play or Sunday school class, use a group kiosk.