The U.S. Energy and Commerce Committee has sent letters to 34 companies, including Twitter, Facebook and FourSquare. They are asking the details of their data collection and usage in order to make sure Apple is protecting the personal information of iOS users.

“Following recent reports that apps could collect address book information and photos without notice and consent from users of Apple’s mobile devices, the members are seeking to better understand what, if any, information these particular apps gather, what they do with it, and what notice they provide to app users,” read a statement by the committee. “The members want the information to begin building a fact-based understanding of the privacy and security practices in the app marketplace.”

Source: AllThingsD