Trusted
http://blogs.windows.com/windows_phone/b/wpdev/archive/2013/10/14/introducing-windows-phone-preview-for-developers.aspx
Installing on my Vodafone Lumia 820 right now.
- Support for 1080p display for new devices like the Lumia 1520
- Support for new processors including Qualcomm’s Snapdragon MSM8974 quad-core CPU
- Close apps by tapping on the X on top right in multitasking view. The icon of the app appears below.
- Custom tones for text or IM, voicemail, email and reminders (confirmed earlier by Windows Phone Central)
- Better storage management: New storage settings make it easier to free up space on your phone and manage temporary files. A new category view shows what's taking up space at a glance.
- Screen Rotation lock: When auto-rotate screen is off, your screen will stay in the current orientation when you rotate your phone.
- Driving Mode: Turns of all notifications except texts and phone calls when you're driving. You can also turn calls and texts off completely or set Driving Mode to text and automatic reply like "Hey, I am driving right now. I'll reply you later." Driving Mode can start automatically when your phone connects to a Bluetooth device.
- Connect to Wi-Fi in OOBE when switching on your new phone for the first time or after you your reset your phone, so you can restore your data even before connecting to a cellular network.
- Attach Office files (.doc, .xls, .ppt) and .pdf files in email.
