We have added a new "Encrypt PDFs with a Password" option to the template settings. If you check this checkbox and set a password, DocSpring will encrypt your generated PDFs. Encrypted PDFs can only be viewed if you enter this password.
Please note: We have not yet added support for "owner passwords", which allow you to define restrictions for the document (printing, changing the document, filling of form fields, etc.) Please contact firstname.lastname@example.org if you would like us to also add support for owner passwords.