Talking to your smartphone has become part of the culture. No, I'm not talking about talking to someone on your smartphone—I'm talking about talking to the phone itself. It started with Siri, which was soon followed by Google Now. Cortana is about to join the party, the new digital assistant unveiled in the beta of Microsoft's Windows Phone 8.1 operating system in early April. Like Siri (but unlike Android's Google Now feature) Cortana has a "personality." You can get Cortana (as part of Windows Phone 8.1) now if you sign up as a Windows Phone developer. The final version of Windows Phone 8.1 is scheduled to launch on June 24.
When designing Cortana, Microsoft explicitly set out to incorporate the best features of Siri with the best of Google Now, while also adding capabilities not found in either. The company polled actual human assistants to see what made them work effectively. One result of this is Cortana's Notebook, which stores the phone user's interests (favorite sport teams or performers for example) and important contacts (called "inner circle").
Siri and Cortana differ from Google Now not only in the attempt at personality—you can famously ask each of those things like "Do you love me?" I've made a little video of asking Cortana a few impertinent questions, for your viewing pleasure. Unlike Android's assistant, Siri and Cortana don't listen to you all the time, waiting for the input command: Instead, you use a hardware button to summon them. You can turn off Google Now's constant listening in settings, but it's on by default, and the service is less useful without it.
Siri and Google Now still have a head start on Cortana, which hasn't even officially released out of beta yet. Each of these sister features uses speech recognition after you invoke and talk to it. Each then parses your words into a question, sends the result to a Web service, and speaks or displays an answer. It's actually fascinating to see Cortana correct its initial voice-transcription to more sensible questions before your eyes. Each service then sends your input to its high-powered servers, and responds with info or the appropriate action—such as starting a text message or delivering a sports score.
So that you can differentiate between what each of the mobile platforms' digital assistants offer in anticipation of Cortana's release, we offer the comparison table that follows.
| Feature Comparison of Cortana, Google Now, and Siri | |||
| Cortana | Google Now | Siri | |
| Summon with hardware button | Yes | No—always listening for "OK Google" | Yes |
| Web search | Yes | Yes | Yes |
| Predictive notifications (e.g. traffic on your commute is bad) | Yes | Yes | No |
| Geofencing (e.g., reminding you to make a purchase when you're near a business) | Yes | Yes | Limited |
| Event or contact based notification ("when your sister calls, tell her happy birthday") | Yes | No | No |
| Call or text contact Name | Yes | Yes | Yes |
| Make calendar appointment | Yes | Yes | Yes |
| Set interests (favorite sports teams, e.g.) | Yes | Yes | No |
| Check weather | Yes | Yes | Yes |
| Daily summaries of info of interest to you | Yes | Yes | No |
| Directions | Yes | Yes | Yes |
| App integration: start app | Yes | Yes | Yes |
| App integration: internal app functions such as post to Facebook or add to Hulu queue | Yes | Yes | Yes |
| Answers sassy questions like "Are you sexy?" | Yes | No | Yes |
| Play music by artist or genre | Yes | Only for Play Music subscribers ($9.99/mo.) | Yes |