So, the chances of a roosterteeth.com app coming to the Xbox is very high. I wouldn't be surprised if there working on it/developing it right now!
Other entertainment websites like Machinima and IGN have apps on the Xbox. If it was to come to the Xbox, it would go to Playstation and other services they could get it on as well.
If you want someone to ask, look to @Adam, Head of Technology!