Samsung has just started to push Galaxy S4's (GT-I9505) firmwares to the KIES server as the device is soon going to be launched in various countries. Samsung always releases the firmware before the device itself and it's the same case with the Galaxy S4, as well. The firmware is based on Android 4.2.2 Jelly Bean with Samsung's Nature UX 2.0 running on top of it. Currently, Samsung has only released the firmware for Germany, we hope other countries to follow soon.
Firmware Details:
Android Version: 4.2.2 – Build JDQ39
PDA: I9505XXUAMDM
CSC: I9505OXAAMDM
All the Galaxy S4 (GT-I9505) firmwares are available for download from our Firmware Section. Now as the official firmwares have been released, it's going to rain custom ROMs and custom kernels for the Galaxy S4 (GT-I9505).