If you want to know precisely when your favorite YouTube channels post a new video -- and I mean the very second -- Tube Alert (free with in-app purchase to remove ads) is for you.
Tube Alert is a stand-alone app that lets you subscribe to your favorite providers and receive a notification whenever they publish something new. When you watch a video on Tube Alert, you can comment, like and share just as you do with the YouTube app.
When you do thinks like comment and share, you earn "Tube Points," which is a virtual in-app currency that can be spent in the Tube Alert Store (still in beta). As of this writing, the store isn't very full-featured, but it will eventually let you exchange points for gift cards and coupons for products that channel operators or other relevant brands make available.
It's an interesting idea, as I don't want to miss a single video from Tolarian Community College for example, but the store seems kind of...not my cup of tea.
If you're interested in checking it out, Tube Alert is available from the App Store now.