Vortex

Vortex is a new and interesting take on game streaming. The interface is simple but streamers are able to customize their stream to give you a more entertaining experience. Vortex doesn't have a PC site but you're still able to watch some great games from PC or console. 

Since this is a mobile-only app, all of the consideration was given to viewers watching from mobile. This has given them the ability to really clean up the streams and optimize them for a great mobile experience. Its feed is well thought out and gives you some excellent recommendations if you're just browsing.