Ranker, an L.A.-based digital media firm boasting 40 million monthly visitors, on Monday morning released Watchworthy, a service that uses machine learning to give users bespoke what-to-watch recommendations. Watchworthy will initially be available only on the iOS app store, but Chief Executive Clark Benson told dot.LA that the company plans to roll it out to Android and connected devices like Roku and Apple TV later this year.