With List Form, the user experience is much better.Below I have logged in as a read-only user and click to view a submitted item. The Edit button is disabled on the ribbon just as you’d expect.
This means you cannot use Nintex Workflow to update these fields.
This is because the submitted form is stored as an XML document, and the promoted fields contain an XPATH expression to the appropriate elements in the XML document. For example, in a console app, I was able to read the values from the promoted fields but could not set them.
The unique list item ID is automatically generated by Share Point and your form does not need to worry about it.
Below is the screenshot of viewing a submitted form in a Form Library: The list and the library are in the same site, and the site uses OOTB branding.
With Info Path List Form, during development you would publish the form to the target list using Info Path Designer.