Cortana is Microsoft's answer to Google Now and Apple's Siri. Its launch coincides with the arrival of the Windows 10 operating system, where it comes built-in, although it becomes more portable and helpful with the use of its official Android app.
With this assistant, you can send commands or questions with your voice or the virtual keyboard. It uses your browsing preferences, current location, and installed apps to respond. This way, you can ask questions that can be searched for online (through Bing, also owned by Microsoft), or have Cortana perform more difficult actions like saving reminders or editing your contacts.
Using the geolocation system on your device, Cortana can suggest nearby attractions or the fastest way to get to a certain place. Thanks to Cortana's card system, you can see all sorts of information on the main menu, just like a homepage, including local news and weather.