http://ssd.iykpqm7jiradoeezzkhj7c4b33g4hbgfwelht2evxxeicbpjy44c7ead.onion/ps/module/how-use-whatsapp-android
Existing WhatsApp users at the time of the privacy policy switch had a grace period to change their settings and prevent Facebook from suggesting friends or serving ads based on WhatsApp data. New accounts, however, do not have the option to refuse these expanded uses of their data. Instead, the only option available to new users is whether to join WhatsApp at all under the new privacy policy and all of the data sharing it entails.