Ask HN: Content moderation for Google Play: what do apps like Vine or MeetMe do?

We are making an Android app that initially will have about 3500 new user profiles created and edited per day, that will be visible to the new users. User profiles contain a thumbnail and a line of text. Google can permanently ban the app from the Play Store for porn/NSFW user profiles. Apparently many apps such as Instagram, MeetMe, MoCoSpace, etc have this problem, but they have no apparent NSFW content. How do they moderate their content in real time? Do they pay their employees/contractors for moderation, or is this moderation community-based? What are the recommended services to moderate this content?