Select the Close text link in the screen header.
Type in the word Yes into the pop up window and select the Continue button to log out of the check-in app.
Please note - If you have un-synced data the check-in app will warn you that any un-synced data will be lost if you choose to log out.
Simply reconnect your device to the internet over Wifi or a data connection if you would like to sync any queued data back to your event dashboard before logging out.