What’s new in Windows Phone 8 update 3?
Support for bigger, higher-resolution screens.
Start screens with room for six Live Tiles.
support for the Qualcomm Snapdragon 800 quad-core processor.
Driving Mode feature.
New accessibility features.
Improved Internet Sharing.
custom ringtones for instant messages, emails, voicemails, and reminders, contacts for text messages.
new rotation lock option.
New storage settings.
Easily close apps.
now connect to Wi-Fi during phone set up.
Note: Microsoft has also announced the Windows Phone Preview for Developers.