Having been the subject of questions regarding its collection of user locations in the past, Apple has been sent a letter over concerns that developers may be accessing and storing user data on its products.

House Energy & Commerce Committee Chairman Henry Waxman and Commerce Manufacturing and Trade Subcommittee Chair G.K. Butterfield sent a letter to Apple on Wednesday, following complaints that the smartphone application Path was collecting address book data and storing it on remote servers without permission.

Whilst Path’s CEO Dave Morin apologised for the actions of its app and moved to introduce a new notification which alerts users to the fact that it would access and store contact data, it brought into question how other app developers accessed the data and how they utilised it.

Sensing a huge public response, Instagram silently updated its app to request data access when matching contacts.

In a letter to Apple CEO Tim Cook, the legislators state:

This incident raises questions about whether Apple’s iOS app developer policies and practices may fall short when it comes to protecting the information of iPhone users and their contacts.

Butterfield and Waxman then quote parts of Apple’s iOS developer website which states that Apple provides a comprehensive collection of tools and frameworks for storing, accessing and sharing data. It is then questioned whether Apple requires apps to request user permission before transmitting data about a user.

The letter then quotes Dustin Curtis’ article, Stealing Your Address Book, which states: “there’s a quiet understanding among many iOS app developers that it is acceptable to send a user’s entire address book, without their permission,” and a report that app developers may stores the contact details for Mark Zuckerberg, Larry Ellison and Bill Gates.

Using those pieces as a reference, Butterfield and Waxman state that because Path was able to gain approval to the App Store, there might be truth to claims of nefarious contact list access and data storage. They state that in order to understand and assess the claims, they ask Tim Cook — or Apple — to answer the following questions:

Please describe all iOS App Guidelines that concern criteria related to the privacy and security of data that will be accessed or transmitted by an app.

Please describe how you determine whether an app meets those criteria.

What data do you consider to be “data about a user” that is subject to the requirement that the app obtain the user’s consent before it is transmitted?

To the extent not addressed in the response to question 2, please describe how you determine whether an app will transmit “data about a user” and whether the consent requirement has been met.

How many iOS apps in the U.S. iTunes Store transmit “data about a user”?

Do you consider the contents of the address book to be “data about a user”?

Do you consider the contents of the address book to be data of the contact? If not, please explain why not. Please explain how you protect the privacy and security interests of that contact in his or her information.

How many iOS apps in the U.S. iTunes Store transmit information from the address book? How many of those ask for the user’s consent before transmitting their contacts’ information?

You have built into your devices the ability to turn off in one place the transmission of location information entirely or on an app-by-app basis. Please explain why you have not done the same for address book information.

Butterfield and Waxman give Apple until February 29 to answer the questions, hoping to work out if Path’s previous data requests are something that consumers should be worried about.

It is not known the answers to these questions will ever become clear but we will be watching for Apple’s response, if it is ever made public. Congress wants clarification, as do most iOS device owners who have read reports over the unauthorised collection and storage of user data.

If you are interested in finding out which of the top iOS apps collect your data, check out our detailed report here.

The letter in full:

Mr. Tim Cook Chief Executive Officer, Apple Inc. 1 Infinite Loop Cupertino, CA 95014 Dear Mr. Cook: Last week, independent iOS app developer Arun Thampi blogged about his discovery that the social networking app “Path” was accessing and collecting the contents of his iPhone address book without ever having asked for his consent.[1] The information taken without his permission – or that of the individual contacts who own that information – included full names, phone numbers, and email addresses.[2] Following media coverage of Mr. Thampi’s discovery, Path’s Co-Founder and CEO Dave Morin quickly apologized, promised to delete from Path’s servers all data it had taken from its users’ address books, and announced the release of a new version of Path that would prompt users to opt in to sharing their address book contacts.[3] This incident raises questions about whether Apple’s iOS app developer policies and practices may fall short when it comes to protecting the information of iPhone users and their contacts. The data management section of your iOS developer website states: “iOS has a comprehensive collection of tools and frameworks for storing, accessing, and sharing data. . . . iOS apps even have access to a device’s global data such as contacts in the Address Book, and photos in the Photo Library.”[4]The app store review guidelines section states: “We review every app on the App Store based on a set of technical, content, and design criteria. This review criteria is now available to you in the App Store Review Guidelines.”[5] This same section indicates that the guidelines are available only to registered members of the iOS Developer Program.[6] However, tech blogs following the Path controversy indicate that the iOS App Guidelines require apps to get a user’s permission before “transmit[ting] data about a user”.[7] In spite of this guidance, claims have been made that “there’s a quiet understanding among many iOS app developers that it is acceptable to send a user’s entire address book, without their permission, to remote servers and then store it for future reference. It’s common practice, and many companies likely have your address book stored in their database.”[8] One blogger claims to have conducted a survey of developers of popular iOS apps and found that 13 of 15 had a “contacts database with millions of records” – with one claiming to have a database containing “Mark Zuckerberg’s cell phone number, Larry Ellison’s home phone number and Bill Gates’ cell phone number.”[9] The fact that the previous version of Path was able to gain approval for distribution through the Apple iTunes Store despite taking the contents of users’ address books without their permission suggests that there could be some truth to these claims. To more fully understand and assess these claims, we are requesting that you respond to the following questions: – Please describe all iOS App Guidelines that concern criteria related to the privacy and security of data that will be accessed or transmitted by an app. – Please describe how you determine whether an app meets those criteria. – What data do you consider to be “data about a user” that is subject to the requirement that the app obtain the user’s consent before it is transmitted? – To the extent not addressed in the response to question 2, please describe how you determine whether an app will transmit “data about a user” and whether the consent requirement has been met. – How many iOS apps in the U.S. iTunes Store transmit “data about a user”? – Do you consider the contents of the address book to be “data about a user”? – Do you consider the contents of the address book to be data of the contact? If not, please explain why not. Please explain how you protect the privacy and security interests of that contact in his or her information. – How many iOS apps in the U.S. iTunes Store transmit information from the address book? How many of those ask for the user’s consent before transmitting their contacts’ information? – You have built into your devices the ability to turn off in one place the transmission of location information entirely or on an app-by-app basis. Please explain why you have not done the same for address book information. Please provide the information requested no later than February 29, 2012. If you have any questions regarding this request, you can contact Felipe Mendoza with the Energy and Commerce Committee Staff at 202-226-3400. Sincerely, Henry A. Waxman, Ranking Member G.K. Butterfield, Ranking Member Subcommittee on Commerce, Manufacturing, and Trade

Read next: Building location-based social networks in Egypt