There are apps that sometimes request your permission to grant them access to your contacts. For example if you download a VoIP app or a messenger app or a social networking app, it sometimes asks for access to your contacts to help you find friends, create a phonebook, and so on, and for the most part it makes sense.
However there are some who abuse the access and actually takes that information and sells it to marketers and advertisers. However for iOS users, it seems that Apple has had enough. The company has recently made some changes to its App Store rules last week where they are limiting how developers and apps make use information about the user’s friends/contacts.
Apple has been promoting its stance on protecting the privacy of their users, especially in this day and age where we’re seeing a lot of privacy-related scandals, especially from huge companies such as Facebook. The change to the App Store’s rules also means that developers caught selling contact information will be banned.
It is unclear as to how Apple plans on enforcing those rules or how they will check, but we suppose at the very least there are measures put into place that could discourage developers from heading down that path.