Plex Essentials - Unofficial App Store
One of the features I missed from XBMC after I done the transition to Plex was the ability to add apps/plugins and customisations. Now I get that Plex's goal is different to XBMC's ie. the later is to be the jack of all trades and the former is a more refined experience, but sometimes it's nice to be able to add a few more things and make it your own. If you've used Plex you'll know that "Channels" (found on the main menu) is in fact a method in which to access features which can be added to Plex which are not part of the core app. I think out of the box you can add features like BBC iPlayer and Youtube, which are must have's for any serious media center. If you need more than this, like say for instance a "Channel" which allows you to forcefully update your library remotely, then the Unofficial App Store is the way to go. More instructions on how to enable this are at this forum post: https://forums.plex.tv/index.php/topic/25523-unsu