Kiosk mode runs your survey in a loop—so each time someone finishes the survey; the survey is ready for the next person to take.
This mode would be used if for instance you were holding a workshop and wanted everyone at the workshop to complete the same survey. You could hand the same iPad around the room and get everyone at the workshop to complete the survey. The Survey will reset it self to the start after each person has submitted the survey.
The default setting is No.