I have created a workflow in VS which doing some logic. I would like to add some configurable text field so that the SharePoint administrators can change it.
For example this is a text field with the name "EmailAddress". An administrator sets this field to some email address (e.g. firstname.lastname@example.org). If the workflow starts, one of the steps is to send an email. This will be the configurable email address.
This field must be available in SharePoint, somewhere at the workflow instance.