The attendee app landing page includes a Sign in With Email option. After typing an email address, a confirmation email is sent. After approving the device, any events a person has been invited to join on the app will appear on the list.
Joining an event
Tapping on an event will bring up more information. If an event is available at that moment, the attendee or staff member will be able to join.
Keep in mind that an upcoming event might not yet be published, meaning that attendees need to wait until it is before joining. On the other hand, it is only possible to join past events before their expiry date.