Apple has pledged to block apps from accessing user address books after accusations that several social network apps were copying contact lists, including names, phone numbers, email addresses and other details, without requesting users permission. 　　The practice came to light when a user of the social network called Path accused the company for copying contacts from his iPhone without his consent. It turns out that many social media apps that can be download at Apples iTunes, including Facebook, Twitter, FourSquare, Instagram, Foodspotting and Yelp are also reported to access users address book. 　　Access to the address book is usually enabled when users click on the "Find Friends" feature on smartphone apps. 　　Even though Social networks said that data taken from smartphones is used only to identify contacts who used the same service and notify the user, two US congressmen asked Apple to explain why the firm allows the practice on its iPhone, as it violates app developer guidelines. 　　One of the biggest social media, Twitter, has admitted copying entire address books from smartphones and storing the data on its servers, often without customers' knowledge. The company has promised to update its app in the wake of the disclosure and clarify its privacy policy for users.