HBO Go, requires that you have a cable subscription. HBO Now, is the equivalent streaming service that does not require cable. It "now" must be purchased through a 3rd party such as itunes, amazon, etc. Note that Tivo has a HBO Go app, but not HBO Now... so if you've cut the cord, what to do? Use Amazon Video. I was able to sign up for HBO Now via Amazon, and instantly the HBO content was available via the Amazon app on my Tivo as though it were Amazon content. Works great and does not require a dedicated HBO app. Game of Thrones streaming on Tivo. Hope that helps people out there.