(CNN) -- Apple on Wednesday said it will start requiring mobile apps to get explicit permission from iPhone and iPad owners before the apps collect and store information about users' personal contacts.
The statement came after a week of revelations that popular social tools like Twitter and Path were doing just that -- sometimes without the user even knowing it.
"Apps that collect or transmit a user's contact data without their prior permission are in violation of our guidelines," Apple spokesman Tom Neumayr said in a written statement to CNN and other media outlets.
"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."
Privacy concerns over the issue were touched off last week when a Web developer blogged about his discovery that Path, an emerging social app that limits users to 50 friends, was uploading his iPhone address book to its servers.
In the aftermath of that revelation, Twitter acknowledged that its "Find Friends" feature also stores user contacts on its servers.
Twitter has said that it will update the language it uses on the site to make it clear what will be done with that information -- which helps new users find friends who are already using the site.
Meanwhile, Path CEO Dave Morin, a former Facebook employee, told Wired, a CNN content partner, that the company "made a mistake." He also said that his app's entire premise, which involves identifying a users' closest friends, requires access to their contacts.
"We don't want to connect you with just anyone on Path," Morin told Wired. "Without the contact list information, some of these features just don't work."
Path has since updated its app to expressly request permission to collect and store contact lists before doing so.
While Path and Twitter have been at the center of this particular instance, privacy has become a constant concern for some across many of the Web's most popular sites.
Google collects reams of data from the users of its array of products (which include Gmail, YouTube, Google Reader and Google+) and Facebook does as well. Virtually every site that does so says it's in order to improve user experience. But unspoken in that explanation is often a desire to more effectively target advertisements.
Neumayr, the Apple spokesman, did not say when the update to Apple's iOS operating system is expected.