You must delete all of a user's data you have received from us (including friend data) if that user asks you to, unless you are required to keep it by law, or it has been aggregated or anonymized so that it cannot be associated with a particular user.
This gives Facebook users a contractual right to have their data deleted from third-party apps, which is a meaningful consumer protection especially for apps they no longer use.
Meta's Platform Terms directly affect consumers because they determine what third-party apps and developers can do with personal data obtained from Facebook or Instagram, including profile information, friend lists, and activity data. The terms prohibit developers from selling platform data or using it for surveillance, but enforcement depends on developer compliance rather than Meta directly protecting users. You can review and remove third-party apps that have access to your Facebook account by visiting Facebook Settings, then 'Apps and Websites', to revoke permissions for any app you no longer trust or use.