Everyone with a PS4 has been patiently waiting for Sony to release the HBO Go app. Finally that time is here, and just in time for season 5 of Game of Thrones. The app on the PS4 works just as it did on the PS3. According to Sony "the app functions just like the PS3 version. After you authenticate your PS4 with your current cable/satellite service through HBOGO.com/activate, you'll be able to watch every episode of HBO's best shows, including True Detective, Silicon Valley, and Game of Thrones."
The only question this brings up, is where in the development process is HBO with the standalone streaming app. A while back we got the news that HBO would be taking themselves into it's own standalone realm, so those of us without a cable subscription could get the service. HBO previously said they would have this service available before season 5, but it is still in the works.