If you already own a Roku device, adding an HBO subscription is easy. Simply open up the Roku Channel, go to the Premium Subscriptions row, and select "HBO". Along with GoT, you can catch the new seasons of Barry, Veep, and Last Night with John Oliver. Full seasons of older HBO series such as Sex and the City, The Sopranos, and Entourage are also available to stream.

Roku, which rose to fame for letting cordcutters watch hundreds of free ad-supported shows on its streaming players, is struggling to keep up in the rapidly expanding world of online streaming. Nearly 11 years old, Roku is now in competition with newer streaming device offerings by Amazon, Google, and Apple. In an effort to stay ahead, Roku launched its premium subscriptions service back in January, allowing viewers to tack-on Showtime, Starz, and other channels for an added fee. The addition of HBO will surely make that lineup all the more attractive.