Apple on Monday revealed what it's been working on in artificial intelligence at its annual Worldwide Developers Conference in Cupertino , Calif. WWDC showed off demos of its redesigned Siri , which can speak back and forth with the user, a major improvement over previous versions of the assistant. In a demo, Siri was able to check concert dates, set a reminder to buy tickets, and even get directions to pick up a friend on the way to the concert venue. But the announcement also highlighted that