To aid in its uphill battle against Apple and Android, Microsoft is adding a voice assistant of its own to Windows Phone 8.1 and according to the latest details she could pass as Siri’s sister.
Inspired by AI character from the Halo series, Cortana will replace Bing-search in the update and act as a mix between Siri and Google Now, according to the Verge, but the UI and personality will be pretty similar to Siri: