If you use Google Tag Manager to handle your analytics, you can add it to your form using a custom analytics script (Pro and Agency plans).
To add Google Tag Manager (GTM) to your form:
If you haven't already, follow Google's instructions for setting up a GTM account and container.
Select the container in your Google Tag Manager account, then navigate to Admin → Install Google Tag Manager.
Back in the Paperform editor, navigate to Configure → Analytics, and find the "Page load scripts" section.
Copy the two code snippets from the install page of GTM.
Paste both of them into your form's "Page load scripts" section.
Any tags and triggers you have set up in GTM should now run on your form.