Without a substantial body of emails, searches, and other contextual information to pull from, over time, it's difficult for any digital assistant to provide proactive assistance. This factor alone inhibited our ability to fully cross-compare Cortana, Google Now and Siri. And keep in mind that although these digital assistants were built with "natural language" in mind, certain phrases aren't recognized: "tweet hello" and "tweet on Twitter hello" weren't recognized by Google Now. "Update Twitter hello" is, but do users recognize that?
At this point, however, we can definitively state that at this point Siri lacks the proactive, "I'll help you before you even ask" intuitive powers of Google Now and Cortana. This puts it at the bottom of the digital-assistant heap, despite its silver-medal showing in our task testing.
The general rule of thumb is this: The more data you feed a digital assistant, the better it works. Unfortunately, it's almost impossible to reconcile this reality with privacy concerns. But that's the future of mobile computing.
Now let's look at each service in detail.
Cortana: an impressive debut
The beta Cortana appears to be taking aim at Google Now, as the two assistants' capabilities overlap quite a bit. Still, it's great to see Microsoft striking off on its own.
Cortana can be accessed by tapping on its Live Tile or holding down the Search button. Unlike the other two assistants, it will ask you your name and how to pronounce it. (You also have the option of adding something silly, such as "Master," for an "I Dream of Jeannie" effect.)
At startup, Cortana will ask permission to access your email, People, and contacts, as well as your location and even your Facebook account. If you'd like to receive the full Cortana experience, allow this. Via Bing, Cortana also asks for an incredible amount of detail about you and your Facebook friends. Be warned.
Next, Cortana will ask you some personal questions, such as what you like to do in the evening and what types of information interest you most. These are mostly harmless and are used to set your initial interests--topics that Cortana will research for you.
The results appear when you launch the Cortana app: Below Cortana's spinning circle icon, you'll see a "daily glance" of news headlines that have been culled from your stated interests. The top news snippet will usually appear in the Cortana Live Tile. I didn't find this especially compelling, but I'm willing to assume that it will improve over time.
You can add interests whenever you'd like, although there's a limited number to choose from: Daily Routine (traffic and the "daily glance" of news headlines); News (spanning all sorts of topics); Eat + Drink (meal suggestions); Travel (a trip planner); and Weather.
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