You will be able to subscribe to HBO Go (without cable) in April 2015

Seeking an April 2015 launch date that will coincide with the launch of the next season of Game of Thrones, HBO’s standalone streaming service will be made available to consumers outside of a monthly cable subscription. […] HBO hasn’t released any specific details on the cost of subscribing to a standalone service. […] It’s likely that HBO will discuss a more detailed timeline of the standalone service product launch as well as details in pricing and content available on the service in the coming months. It’s also possible that announcements related to supported hardware platforms will pop up during CES 2015 next month. – Mike Flacy,Digital Trends 
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