The alternative media manager, Plex, has announced a new feature, called Plex Home. Plex Home allows multiple user profiles, and more importantly, parental controls.
Version 0.9.11.4 of Plex Media Server supports Plex Home, but your front-end client will have to be updated as well. So far, only Plex Home Theater, Roku, and the Plex Web app support Plex Home. However, we expect updates for iOS and PlexConnect soon.