Microsoft is preparing a Windows Phone 8.1 update that allegedly includes a Siri-like personal assistant.

ZDNet reported that the personal assistant goes by the codename Cortana. That's also the name of a character in the popular video game Halo. Like Apple's Siri, Cortana will enable Windows Phone users to navigate and interact with a handset via voice commands.

Although Windows Phone currently features some voice command functions, Cortana is apparently a more feature-rich adaptation. Microsoft's Steve Ballmer once wrote in a blog post that his company is working on a "family of devices powered by a service-enabled shell" - and ZDNet has subsequently claimed that Cortana is "core to the makeover" of the entire shell.

Read: Windows 8 tablet ad pokes fun at Siri on the iPad

Microsoft purportedly plans to make Cortona central to future versions of Windows Phone, Windows and the Xbox One operating systems. The Verge even published a few screenshots of Cortana, revealing how Microsoft is testing weather information, local information, notifications, access to Bluetooth controls and calendar events under a "single central interface".

Check out Cortana below.