With today's update to Soapbox, you can now add custom fields to an online petition. These custom fields write directly to Salesforce and augment the existing standard fields included in the Petitions app, allowing you to get exactly the information you need from your supporters.
For more details, check out these knowledge base articles:
- Add custom fields from Salesforce to a Petition
- Reorder Custom Salesforce Fields on a Petition
- Prepopulating Custom Salesforce Fields on a Petition with data from the logged in user's Salesforce Contact record