Microsoft's purported Cortana voice assistant is a combination of Siri and Google Now functionality that will replace Bing search feature after the Windows Phone 8.1 update.

Microsoft rolled out a few updates to its emerging mobile OS, Windows Phone, but there have been no significant changes to the OS since the launch in October 2012. The latest update, Windows Phone 8.1, is likely to change this perception as the software giant is reportedly launching Cortana, personal voice assist feature for Windows Phones along with other changes. Sources revealed to The Verge that Cortana will be a replacement to its current Bing search feature.

Cortana, which takes its name after Microsoft's popular Halo game series, will combine the best of Apple's Siri and Google Now's functionalities. It will put aside the Bing search feature, which relies on a dedicated physical key and activate voice commands to pull up information from sources like Foursquare, Bing and others.

Microsoft will also address the data security concern with a new feature called Notebook. This will allow Windows Phone users to control what information is shared with Cortana and also modify or delete information stored in it. The Notebook feature will allow Cortana to access information such as location data, behaviors, personal information, reminders and contact information, according to the report.

The digital voice assist, much like iPhone's Siri, will answer users' questions, address the owner by name, set reminders and search queries by voice or text. In addition, Cortana will act as a smart assistant and react to messages and emails with phrases like "let's meet tomorrow at 8PM" and offer to set up a reminder for the date. The sources also revealed that Cortana will blend in with the phone's theme featuring a circular animated icon with the matching color of the selected Windows Phone accent. The voice assistant will be animated and show emotions based on the user's queries.

The integration of Cortana in Windows Phone 8.1, which is expected to arrive in the coming months, will receive a hearty welcome but for Microsoft to succeed with big players like Apple and Google, the company must integrate the feature into third-party apps and other products like Xbox One.