Although Apple has stated to Reuters that, "Apps that collect or transmit a user's contact data without their prior permission are in violation of our guidelines", the company is still taking action to ensure that app developers on its various iOS devices seek "explicit permission" before accessing user address book data.
"We're working to make this even better for our customers, and as we have done with location services, any app wishing to access contact data will require explicit user approval in a future software release," said Apple in the States on Wednesday.
According to Reuters, "In a letter addressed to Apple Chief Executive Tim Cook, Representatives Henry Waxman of California and G.K. Butterfield of North Carolina, both Democrats on the House Energy and Commerce Committee, asked Apple earlier on Wednesday to clarify its developer guidelines and the measures taken by the company to screen apps sold on its App Store."
Apparently "apps like Facebook, Twitter, Foursquare and Foodspotting similarly uploaded user data -- without permission, in some cases."
Apple had until February 29 to respond to the letter.