500px
TechCrunch was the first to report the news based on an interview with 500px's COO Evgeny Tchebotarev.
Tchebotarev defended the app, telling TechCrunch that developers put safeguards in 500px to make it tough for people to find nude photos without changing special settings on the company's website first. Plus, it's against 500px's policy to allow pornographic photos. Most nude photos are artistic.