In an effort to better capitalize the media companies using the App Store as another channel to reach out users, Apple has taken a number of steps in the past few months, some more controlling than others.  First there was the 30 percent fee on digital content purchased via the platform, followed by a now-defunct rule requiring developers to charge just as much for content on third party sites as they do in the App Store.

And now it seems that over the weekend Apple has begun enforcing a policy that dates back to February, that prohibits developers from providing in-app links to their own out-of-app content. Kobo, Borders, Nook Kids, the Kindle Apps and Google Books (which was temporarily pulled from the site) were all hastefully updated to comply with the new polices in the past few days.

“The changes will cut the amount of digital content available for easy purchase from within the App Store, reducing its appeal to consumers and potentially limiting sales for third-party app developers,” reports Financial Times.

Users of the apps subject to Apple’s restrictions will have to purchase content directly via Safari, which can make things a lot more complicated for apps like Spotify and Rhapsody, which require a subscription. It turns out, this update can also result in some usability issues, too, according to tech blogger Martin Taylor. Kobo books purchased via a browser could not be viewed from the publication’s own app.

Apple is looking to get out the most out of the major publications that target its mobile consumer base, although this is not the only field that seems to have caught the company’s eye. Reports suggested that Apple may be one of the buyers interested in acquiring Hulu, though the potential deal seems to have since cooled off.  But it’s clear that Apple’s steadily looking to center its own ecosystem in the mobile space, especially when it comes to media and software distribution, along with the personal cloud.