In another sign that Apple is having difficulty controlling the content in its App Store, the company has banned an iPhone application for reportedly featuring explicit pictures of a 15-year-old girl.

The "BeautyMeter" app enables iPhone and iPod Touch owners to view user-submitted photos and rate them based on various body parts and clothing. The program shows pictures of women and men in various states of undress. Before it was pulled from the App Store Thursday it featured a picture of a topless 15-year-old female.

Apple controls and vets every app that gets into its App Store, and it has a clear policy against pornography or explicit content. BeautyMeter was likely approved by Apple because when it was submitted it did not feature explicit photos. Later the app pulled images from a third-party server.

As content creators are eager to target the more than 40 million iPhone and iPod Touch owners, this may become an increasingly important issue that Apple has to deal with. Less than a week ago, the company removed the "Hottest Girl" from the App Store because it featured pictures of topless women. Like BeautyMeter, Hottest Girl app did not include nude pictures when it was first approved by Apple.

Some developers have said Apple's vetting process for the App Store is arbitrary or unfair, as a South Park app wasn't allowed in due to its explicit language but apps like BeautyMeter and Hottest Girl were approved. The iPhone 3.0 software may give Apple a little more leeway with what it approves because it includes an age-verification process and parental controls.

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