Web/iOS/Android: The TV is appealing because you don't need to think about what to watch. By default, finding videos on YouTube isn't as straightforward. 5by makes finding good YouTube videos easier by recommending videos based on your mood or what you're up to at the time.
The 5by Concierge shows videos sorted by function. There are categories like, "Hip Stuff", "Showing Your Friends", "Killing Time", "Geeking Out" and "Making You Laugh". The recommendations are based on your mood, and so require less thinking than YouTube's default recommendation engines. Similar to YouTube, 5by allows you to save Favourites and view your History.
5by's mobile apps for iOS and Android still has the interesting recommendations, with a few social networking features. You can chat privately with friends and share videos.