Previously, Facebook reportedly announced at the F8 developer conference that it will take the full advantage of the secrecy surrounding how Apple's App Store and Google Play store on Android rank and feature apps that are favorites of the developers.

But Apple made a minor change in its App Store indicating a simple warning to Facebook to stay away from such business. Apple initiated such a rule change in a way so that apps within the App Store do not compete with them by promoting other apps or app spam that is encouraging downloads of other apps.

There are some notions that Facebook itself is a mobile app as it carries loads of ads of other apps like Candy Crush Saga seeking the users to promote the app to friends on Facebook to play the game further. Such promotion is what Apple tries to halt.

Apple's App Store is nontransparent while developers add any company that comes by like Facebook. It lets them advertise to new users and promote downloads improving their rank in the Apple App Store.

The rule cited to end Facebook from promoting its own App Center on the mobile app version of Facebook, which is hardly a big deal as the company makes more money from mobile ads for apps than from app downloads. By promoting the Facebook's App Center, it prevents from competing against Apple.

The Business Insider reported Apple has also initiated in sending messages to the developers who are also in the similar category of violating of the new rules.

"We found that your app includes features of content that can have an excessive influence in the listing order or ranking on the App Store, which is not in compliance with App Store Review Guidelines."

Also, the source said Baird Equity Research Analysts Colin Sebastian and Benjamin Gaither warned investors that this would be negative for Facebook.

The changes in the policies are related to Apple's policies stopping the distribution of apps that encourage users to watch video ads or post updates on Facebook in exchange for any kind of benefits.

Apple is striving to become a larger player in the app discovery ecosystem and by putting restrictions will pull down Facebook and app install ads down.

Facebook has been seen as a competition as it has become a larger portion of the company's mobile ad revenues and growth.