On Facebook Apps and Tabs' Privacy Page you can request and collect all the privacy and GDPR related information that Facebook Apps and Tabs is providing.
The privacy policy by is a legal document or statement that discloses how Facebook Apps and Tabs gathers, uses, discloses, and manges their customers' data.
The basis for Fbapp sharing, adding, uploading, hosting, accessing or sending personal data out of Europe. Vendors can also add a description of their own impact assessment for data transfers.