One of my most interesting test cases for Cortana was a reminder to pick up milk when I got to the store, making use of the phone's GPS capability. (Reminders given to Cortana can be made using time or contacts, as well as by location.) I activated Cortana by touching the Cortana tile pinned to the home screen, then touched the microphone and said, "Remind me to pick up milk when I get to the store."
Cortana's voice repeated my request and then showed me a list of the nearest store with milk. I could tap on that store or tap "any store" as well. It then activated a text reminder with a tone alerting me to the text once I was parked a few feet from the entrance to the store.
Later, I altered the command to, "Remind me to pick up milk when I'm anywhere near a store" to make it useful when driving by a store, not actually going to it. But Cortana repeatedly kept changing that request to the older command, which it truncated as, "Remind you when you get to store. Is this the one you want?"
Trivia note to gamers: Cortana's female voice is synthesized in part from an AI character named Cortana (played by actress Jen Taylor) in the Halo video game series. (There is a male voice available as well.)
And there's humor: When you ask Cortana on the phone if she's better than Siri, she comes back with even more Halo insider wisdom, nutty as it is: "Not to brag, but apparently I'm going to help save the universe in about 500 years."
Overall, Cortana isn't everything one might hope for, but it gets a 9 out of 10 in my book. Voice input and response have really come a long way, and represent a major asset for Microsoft, should the company should sell off its smartphone division or make some other drastic move.
Other Windows Phone 8.1 features
There are other Windows Phone 8.1 features that I liked. For example, a new Word Flow feature adds shape writing to the virtual on-screen keyboard (shape writing is a process of drawing on the keyboard with a finger to reach each letter without lifting the finger to touch each letter). Action Center, which handles notifications and other phone settings, and Sense, which manages data and battery use, are two other powerful new additions in Windows Phone 8.1.
To see Action Center, you swipe down from the top of the screen. Four buttons at the top let you control Bluetooth, Wi-Fi, airplane mode, display brightness and more; they can be swapped out with others you find more important. There's also an "All settings" button if you want to view the entire list of settings. Beneath that are notifications of recent emails, messages and headlines.
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