Two months ahead of BUILD 2014 in April, sources reveal that Microsoft is quietly sharing the software development kit (SDK) to Windows Phone 8.1. One source is a developer that took to Reddit to reveal some of the upcoming features. Based on the details, Microsoft is indeed working on merging Windows Phone and Windows RT closer together.
We knew Microsoft would eventually take this path, as Microsoft executive Julie Larson-Green said last year that "we have the phone OS, we have Windows RT, and we have full Windows. We are not going to have three." Another sign was the larger screen sizes added in the most recent Windows Phone 8 update in December, indicating that the mobile OS could be used on tablets.
The leak also shows that Microsoft will allow users to change the default messaging application, similar to the change Microsoft did with the default camera app. There's also a new feature for monitoring and tracking the battery's life, VPN support and the rebranding of SkyDrive to OneDrive. The Music+Videos app will be split into separate Xbox Music and Xbox Videos apps.
Other notable changes in Windows Phone 8.1 include the way the back button now works, putting an app in suspension rather than closing the app altogether (think multitasking). Microsoft has also "tweaked" the camera app, and has removed the Facebook integration. Internet Explorer 11 is now the current browser version, and there's also support for installing apps on SD cards.
A few expected features didn't make an appearance in the recent SDK including the Siri-like Cortana personal assistant as well as the Bing Search, the Action Center and the store.
Windows Phone 8.1 "Blue" is expected to be released during or shortly after Microsoft's BUILD developer conference in April. The company is also expected to release Update 1 for Windows 8.1, bringing new features such as the rebranded SkyDrive cloud storage, the ability to pin Metro apps on the taskbar, and more.
To see a full list of changes coming to Windows Phone 8.1, head here.