(CNN) -- It's been framed as a debate between Web freedom and the freedom from stumbling upon potentially offensive content. In recent weeks, several companies have been forced to grapple with sexually explicit images appearing in their popular mobile apps. Such images, a small fraction of the apps' user-generated content, place these companies at risk for being banned from portals such as Apple's App Store, where millions of people gain access to the mobile Web. But some observers see something more at play here. "In this debate, some may focus on freedom and others may focus on the harm of adult content, but what's really happening here is the crystallization of the power of platform providers -- Apple, Google, Microsoft and even Amazon," said James McQuivey, a tech-industry analyst at Forrester Research.
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Controversy over adult content on mobile apps highlights control over free speech
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Apple has banned some apps from its store because of sexual images
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Tech titans may have more power over Internet free speech than some governments
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Apple promises a mobile experience free from porn and other irritants
That's not to mention the millions more worldwide using tablets and other devices as their main entry point onto the @placeholder.