Developers leak Windows Phone 8.1 SDK, reveal new features

For our full coverage, head to Windows Phone 8.1 SDK leak - All you need to know!

Windows Phone 8.1, codenamed 'Blue', is a forthcoming major update for Microsoft's mobile platform. While we're anticipating an announcement at the company’s Build 2014 conference in April, with new hardware arriving in June, already Microsoft has released the SDK to developers and we're seeing some leaks appear on Reddit, pointing at a handful of new features in the 8.1 update.

The leaks published by developers who have early access to the SDK show signs of further unity between Windows Phone and Windows 8.1, which Microsoft has previously hinted at. Both JavaScript and HTML is touted as being supported for app development, enabling developers on the desktop+tablet OS to bring across compatible content for smartphone consumers to enjoy.

Some obvious changes have been jotted down, including the rebranding of SkyDrive to OneDrive, not to mention the ability to set up and configure connections to Virtual Private Networks (VPN). A number of other changes have reportedly been implemented in the SDK, making multitasking easier with the removal of "X to close" and allowing users to swipe down on each app tile (much like Windows 8.1) – the back button no longer closes apps, but suspends them.

New File Picker

Here's the list of features noted by the developer with Windows Phone 8.1 SDK access:

NEW Audio/video transcoding, Hardware accelerated
NEW Media editing: audio and video; Audio effects, video effects; Slow motion video
NEW Apps can capture audio/video from themselves
NEW Stereoscopic 3d support
NEW Wi-Fi Direct, a Wi-Fi standard allowing direct peer-to-peer connections over Wi-Fi without an access point
NEW Windows Phone 8.1 apps won't run on 8.0 devices until they upgrade
NEW Documentation confirms ALL current Windows Phone 8 hardware to get 8.1
NEW Dev tools: SemanticZoom, DatePicker, TimePicker
NEW PlayTo support
NEW Single sign-in for apps (like on Windows 8) with Microsoft Account; sign in will persist across devices + apps with permissions prompt
NEW YouTube Player (see lede image) including HTML5 video support (video playback doesn't have to be full screen) And you get custom UI, so YouTube Closed Captions are in
NEW File picker (see above image)
NEW Geofencing API for location-based reminders
NEW Background tasks: Bluetooth signal strength, Chat message notification, Device connection change, Device use trigger, Gatt characteristic notification, Location, Push notification, Rfcomm connection, System event, Timer
NEW Slide down to close apps
NEW Navigation bar color selection
NEW USB choices
NEW Updated camera layout, similar to Windows 8.1 (see photo below)
Back button doesn't terminate the app
No more XAP, instead APPX
VPN (Virtual Private Network)
OneDrive (previously SkyDrive) with integrated file browser (just like Windows 8.1)
Filter through installed apps by usage/install date
Select multiple tiles when customising the Start screen [FALSE]
More efficient multitasking
Ability to install apps on inserted SD Cards
Internet Explorer 11 improved with WebGL and Normal mapping support
Separate volume controls for ringer, media, etc.
Bing smart search (similar search system as Windows 8.1)
Xbox Music and Xbox Video as standalone apps instead of the Music + Video Hub (allowing more updates to be pushed)
Redesigned Xbox Game Hub
Twitter integrated more deeply into the contacts Hub
Facebook account option REMOVED (updated)
Quick settings access (Wi-Fi, Bluetooth) by doing a quick swipe from the top of the screen
Action Center accessed by doing a full swipe from up to the bottom (separate from the Notification Center)
Silent notifications which go directly to the Action center
Possibility to mark a Live Tile as read by swiping from the left of said tile
Auto-updates for apps (just like Windows 8.1)
Better backup functionality
Improved keyboard
Bluetooth 4.0 LE (to non-Lumia Windows Phones)
Feature to mirror Windows Phone screens to TVs and/or monitors

Things not included in the SDK:

Cortana
Action Center + Notification Center
new gesture-based keyboard

A final interesting note is how Windows Phone is referred to as WinPRT.

We haven't been able to confirm the above list, so be sure to take each entry with a grain of salt. That said, it's looking likely Windows Phone 8.1 will be an impressive update, bringing across much anticipated functionality. Reddit user DDReaper compiled the sweet list, taking everything from other threads and bundling everything in a easily digestible experience.

Source: Reddit; thanks to everyone who tipped us!