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. See Control access to your contacts.
To authorise an app or a website to use information from your contacts, click OK in the dialogue. 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, any information they collect is governed by their terms and privacy policies. It’s recommended that you learn about the privacy practices of those parties.
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.