A really useful feature which some might not be aware of yet is the response change log which is maintained for each submitted response.

When an authorised user edits a response, a record is kept of who made the change, when they made it and what the original value was. That way, you can keep track of any modifications made.

A full audit history is maintained for each field.

To view the response change log, simply click through to view the full response. The change log is shown below a field in red if any changes have been made.