WhatsApp will start sharing data with Facebook to help it in ad targeting,
In spite of the promises,Facebook will get access to your phone number and other data so that it can deliver better friend suggestions and serve targeted ads.
But you’ll be able to stop WhatsApp from sharing any of your info with Facebook
How to stop WhatsApp from sharing your personal data with Facebook
If you mistakenly tap on Agree before you’ve had the chance to disable the feature, you’ll have 30 days to fix it.
Go to Settings, Account,Share my account info inside the WhatsApp app, and then uncheck the box.
That should ensure that your phone number isn’t shared with Facebook, and the rest of your personal data will be safe as well.