Samsung Galaxy S4 LTE (GT-I9505) receives official Android 4.3 update

CHANGES AND IMPROVEMENTS IN ANDROID 4.3 UPDATE
- OpenGL 3.0 Support
 - GALAXY GEAR Support
 - TRIM Support (Makes the device much faster) - ANT+ Support
- Samsung KNOX Implementation (KNOX bootloader and dedicated application)
- Samsung Wallet comes pre-loaded
- Improved RAM management
- Improved Display colour reproduction (Display looks much sharper than before)
- Improved TouchWiz Launcher (Much less launcher redraws and less lag)
- New Samsung Keyboard
- New Samsung Browser (Full screen by default, new tab interface and more)
- New Reading Mode (Optimises display for reading, used by only a few specific applications)
- New Camera firmware
- Minor UI tweaks (Contacts app, Flashlight Widget, dialog boxes etc) The software update is being rolled out in phases, so it may not yet be available in your country at the moment but don’t worry it will arrive very soon. If your device is carrier branded then it might take sometime as the update has to get improved by the carrier first and only then Samsung will make it available for your device.
Download here