Moaform has auto save feature and you can restore or revert the survey with 'Undo' or 'Redo' buttons on upper left. Save status is displayed on the upper left when the form is edited.
There is a progress menu to show creation progress at the upper center of form builder and you can press 'Collect' once you complete editing form to start collecting responses after various configurations.
If the content of the form is edited after response collection began, edited content is auto saved but it is not immediately shown in the response page but only when you press apply changes button on upper right. This is because the survey may appear strange to the respondents if edited content is reflected real-time. Please press apply changes button on the upper right after editing the content of the form while responses are collected.
If you wish to revert to an earlier version when response is collected while editing the content of form collecting responses, press restore button on the upper right.