No longer owned by a cable parent (Time Warner Cable), HBO has become fairly aggressive in fighting back Netflix, Amazon and other premium content providers. They were early to the OTT game, offering HBO GO to authenticated cable subscribers. They have always had a robust VOD library to drive value and retention of their cable subscription model. And they have created a non-cable authentication platform called HBO NOW that will be exclusive to Apple TV for 3 months. You almost need a scorecard to know what content is exclusive to any of these formats: VOD, GO, and NOW.
But even an exclusive HBO NOW offering with Apple isn't stopping HBO from being accessible to the streaming universe. In their latest deal, HBO is offering a streaming package to Sling TV, different from Apple TV. It includes one linear feed to their main channel HBO (not HBO 2,3, 4, etc.) and the cable VOD library and priced to consumers at $15/month. If Apple thought that they had some exclusivity, then they must be feeling a bit cheated. But for HBO, it is an aggressive strategy to drive subscription whether a cable, Apple TV, or Sling TV customer.
So is there any content exclusivity across any of HBO's platforms? Will there be windows where one platform gets a TV series or movie and the others don't. Or will shows like Game of Thrones be accessible regardless of the platform, VOD, GO, or NOW? It may simply be that they are dressed up under different brand extensions but are essentially the same library of content.
Being free of a cable operator has certainly allowed HBO and its other Turner siblings (TNT, TBS, etc) to negotiate deals without the threat of anti-synergy behavior. With streaming access a big competitive threat to the traditional cable model, delivering their linear and on demand library as OTT streams, HBO and Turner are delivering content where and how the consumer wishes to watch it.