You can add to your client applications, hidden/private fields so that your team still get a dedicated space for adding privately any useful information to the application (This information won't be shared with to clients.)
A little locker shows that a line item isn't visible to a client. However, a private line item is still accessible through the collaboration feature and will still be exported with your application.
==How to create a private/hidden line item?==
==How to mark an existing line item/document/file as private?==
When to use this feature?
This feature is useful if you you need to add to your applications internal, confidential documents. An application process is not always about getting information from the outside, this information can also be collected within your organization so in this case, internal/ private line items will allow you to add this information all in one place.
How to switch back an internal line item to visible?
Just click on the 'Edit' button in front of the required line item and untick the 'Display to recipient' option