The updated version of the 500px app includes a new "report" button to flag inappropriate content, a restricted-search function, and is labeled for ages 17 and up, CNET reported Tuesday.
500px, which hosts over 6 million photos, had initially been pulled from the app store for violating Apple's rules against featuring pornographic images and material, Apple said, and some complaints about child pornography.
The company is looking into the child pornography allegations, Tchebotarev said, but added he has yet to receive the alleged pornographic images or complaints from Apple and an internal investigation did not uncover any pornographic images.
Apple said 500px's 17-and-up age classification means the app has "Frequent/Intense Sexual Content or Nudity."
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