Siri, the virtual assistant built into iPhones, launched to great fanfare last October and soon inspired a crowd of copycat apps, heated online arguments about its effectiveness, and an Apple ad campaign in which it played the starring role. Almost a year later, Google's vision of how a smartphone can become a trusted, all-knowing assistant is rolling out to consumers in the form of Google Now. It's a feature of the newest iteration of Android, Jelly Bean, which is so far available on only a handful of smartphones, and suggests that Google has ambitions to go well beyond what Siri has shown so far.
Google Now doesn't have a pretend personality like Apple's sassy assistant, instead just appearing as a familiar search box. But just like Siri, it can take voice commands related to phone functions such as setting reminders or sending messages, and field requests for information such as "How old is the Eiffel Tower?" and "Where can I find a good Chinese restaurant?"
Also like Siri, Google Now responds with speech. However, rather than passing along queries to third-party services such as Yelp for answers, Google's helper makes use of the company's recently launched Knowledge Graph, a database that categorizes information in useful ways (see "Google's New Brain Could Have a Big Impact").
Google Now also introduces a new trick. It combines the constant stream of data a smartphone collects on its owner with clues about the person's life that Google can sift from Web searches and e-mails to guess what he or she would ask it for next. This enables Google Now not only to meet a user's needs but also, in some cases, to preëmpt them. Virtual index cards appear offering information it thinks you need to know at a particular time.