Fast-thinking, always-on listening capabilities
Currently, the Android-powered Moto X is one of the few handsets capable of listening for your command from across the room, but in my experience it seems to work best where there isn't much surrounding noise. It also takes an extra second to launch the Google Now app, translate the message, and then do its duty of processing the query.
Microsoft should take the idea a step further by perfecting the process: Enable the phone to hear a command even in a crowded room, and then allow it to find the answer to the question immediately without launching into another application. Make the process seamless, integrated, and always available, like the voice commands on the Xbox One.
Individual app control
The ability to send text messages, give directions, and launch apps is fine and dandy, but that's not all a digital assistant should be limited to.
Cortana should include the ability to control individual applications. For instance, if you wanted to play a song, you could simply shout out the name of the app you wanted to launch, and then the command for that specific app. This approach could even work interchangeably with various apps of the same type, such as Xbox Music and Spotify, which theoretically could both understand the command "Play playlist, Katy Perry" with one unified API, making it easy for developers to enable this feature in any app. The possibilities are endless.
A better driving mode
It's dangerous to text and drive, but it's also dangerous to reach down and press the button to accept a phone call, even if the call is routed through the Bluetooth-enabled speakers in your car. Although Microsoft already offers a driving mode in the latest Windows Phone update, it could utilize Cortana to let you operate the phone entirely without any finger-to-screen contact.
If you're stuck in traffic, for example, you could command your phone to read you the last three tweets from your Twitter feed. Your Windows Phone could then dictate those tweets to you, along with the usernames. You could even ask it to find another route if you're stuck in traffic, without your having to reach over and pan the screen for the route with more green — that's the most inconvenient thing when you're trying to maneuver around bumper-to-bumper traffic.
A truly next-level feature would have the phone prompt you in certain situations. If traffic is bad and the phone estimates that you won't arrive at your next appointment on time, for instance, it could declare: "It looks like you won't make it to your next appointment. Would you like me to call the associated phone number?" Or how about, "There's just been an accident along your route. Would you like me to find a way around it?"
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