In the past, some developers asked users for access to their phone contacts and used the information for marketing. They may also have shared or sold the data, without permission from the people on the contact list. But the new App Store Review Guidelines prohibit developers from making databases with information taken from iPhone owners' contacts, and restrict them from sharing such a database with third parties, or selling it.
In addition, apps can't get access to someone's contact list and say it's being used for something, then use it for something else, unless the developer obtains consent. Breaking the rules can get developers banned.
In its updated App Store guidelines, Apple says: "Do not use information from Contacts, Photos or other APIs that access user data to build a contact database for your own use or for sale/distribution to third parties, and don't collect information about which other apps are installed on a user's device for the purposes of analytics or advertising/marketing."
A similar practice of sharing friends' data without their permission got Facebook in hot water in March, after political consultancy Cambridge Analytica had improperly received data from as many as 87 million user profiles. Following the scandal, Apple CEO Tim Cook said .
Apple didn't mention the updated App Store Review Guidelines atearlier this month. The company didn't immediately respond to a request for comment.