Siri vs. Alexa vs. Cortana vs. Google Assistant: It's Battle of the AI Systems

They are planning our days, making our reservations, ordering our cars. We talk to Alexa, Siri, Cortana and Google like we would a human assistant. But how do these AI systems compare? Here's a look at what they do, how they're marketed and what they'll do next. Origins: Siri was perhaps the first virtual personal assistant to enter the mainstream, debuting on the iPhone in 2011. Functions: Siri only widely opened to third-party apps this year with the arrival of iOS 10.