Apr 24, 2017 10:22 AM
At this time, the pop-out for adding new Contact cannot be customized with new field options. However, when you start to fill in the fields show, additional fields will appear. These are your default properties that you can adjust in Contact Settings.
Another potential workaround would be to have your users add a Contact through a form. You can add the fields you would like to that form and keep the link to the landing page with that form internal.