Apple is tightening its control of the App Store even further by refusing to allow application developers to sell content within their apps.
In line with the new policy, Apple has rejected Sony's iPhone application that was designed to enable users to buy and read e-books from the Sony Reader Store.
Apple told Sony that from now on, all in-app purchases would have to go through Apple, according to the New York Times.
The move could affect companies like Amazon.com and others that sell e-book readers that compete with Apple's iPad tablet, the paper said.
Until now, iPad users have not needed to own a Kindle to read Kindle books bought from Amazon, but that may now change.
Some analysts believe the move may signal a shift for Apple from making money from devices to getting more value from the platform.
Apple and Amazon declined to comment, the Times said.