HBO has partnered with social network company GetGlue for fans of the premium cable network’s “True Blood” series. With GetGlue, users earn rewards and get recommendations when they check into specific entertainment. In recent months, Universal Pictures, Showtime, Fox and PBS have all linked mobile marketing of entertainment properties with AdaptiveBlue’s GetGlue capabilities. According to HBO, “True Blood” was chosen because it already has a strong fan base on GetGlue. For the first time, AdaptiveBlue is giving coupons with discounts for the show in addition to branded stickers. All fans can get a 10 percent discount in HBO’s online store, fans with a Truebies badge get a 15 percent discount, and those with the Makers badge get a 20 percent discount, with a $50 gift card for Guru. The discounts can be used to purchase “True Blood” memorabilia and DVDs in HBO’s online store.