Microsoft to launch Windows Phone 8 Apollo+ software update in 2013
Into Mobile

Based on information that recently surfaced online via Twitter, it appears that Microsoft has plans to roll out an incremental software update to users of its much-vaunted Windows Phone devices. This software update will be called Apollo Plus, and is expected to bring a number of new features and much-needed bug fixes to phones running Microsoft's Windows Phone 8. There's no word yet on when the new software will arrive exactly but it is rumored to be scheduled for release in Q1 2013.

What Else You Need To Know

  • Microsoft's Windows Phone software is currently on version 8 and uses the codename Apollo, which is where the upcoming Apollo Plus's codename is derived from.

Other sources

It seems that Microsoft wanted to bring even more features to the Windows Phone 8 OS but ran out of time and skipped out on a few features to get the new OS to market. - Kevin Everett, Daily Mobile  
The Inquirer
Microsoft to release Windows Phone 8 Apollo Plus next year  

Tipped to be shown at MWC, arrive late next year

Other
Windows Phone 8 Apollo+ update set for Q1 2013  

The Apollo+ moniker comes from the original codename for Windows Phone 8, which was called Apollo.

Daily Mobile
Apollo Plus Update on it’s Way for Windows Phone 8 Devices
Other
Windows Phone 8 Apollo Plus coming in 2013  

An update for Windows Phone 8 smartphones called Apollo Plus will arrive from Microsoft next year.

Into Mobile
Windows Phone 8 getting Apollo Plus update in early 2013  

The updated software will bring several new features that weren’t fully in scope for the Windows Phone 8 initial release, along with some smaller enhancements