Allow apps to use your contact information
Some apps and websites can use your contact information to provide you with services and features. For example, an app might use your contacts to help you address emails or share messages with friends.
To authorise an app or a website to use information from your contacts, click OK. If you don’t want to authorise the use of your contact information, click Don’t Allow.
If you allow third-party apps or websites to use your contact information, you are subject to their terms and privacy policies and not the Apple Privacy Policy. You should review their terms and privacy policies to understand how they treat and use your information. See the Apple Privacy Policy.
You can review and change your privacy settings using the Privacy pane of Security & Privacy preferences.
Choose Apple menu > System Preferences, click Security & Privacy, then click Privacy.