Samsung Galaxy S4 users who wish to upgrade to the new Android 4.3 can achieve that by following the detailed procedure below. Reports coming from users who have installed it confirm that the Android 4.3 ROM is in absolute stable condition.

This Android 4.3 Jelly bean is a leaked version of the final product which is expected to launch in July, I can’t explain how it got leaked, but I can say it almost identical to Android 4.2 with a minor and maybe few refinements.
Image Credit: itnewsAfrica
Note: 1. Please read our disclaimer before you proceed. Any damages caused by this procedure will be entirely binding on you. By reading and performing this task, you accept.
2. Performing this task will void your warranty.

Hint:
1. Ensure you have a min. battery level of 60%.
2. Your device must be factory Unlocked.

The method is specifically for Samsung Galaxy S4 I9500.
Tip: How To Enable Samsung Galaxy S4 USB Debugging

6 Easy Steps To Install Android 4.3 On Your Samsung Galaxy S4
1. Download Google Play edition ROM for Samsung Galaxy S4
File 1 or File 2 (Choose either one)
2. Copy either of the download file into your internal SD Card
3. Enter recovery mode (Power + Volume Up + Home)
4. Complete a Factory Reset
5. http://www.thatnaijablog.com/2013/07/install-android-43-on-samsung-galaxy-S4.html

cool story bro!

The simplest way to do is download KIES Software and connect datacable on your PC and it will automatically update your OS.

ginoherbert: The simplest way to do is download KIES Software and connect datacable on your PC and it will automatically update your OS.

it's not seeding officially, is it?

ginoherbert: The simplest way to do is download KIES Software and connect datacable on your PC and it will automatically update your OS.

Wake me up when you have done that for an OS that hasn't been officially released. Even when released, don't expect Samsung to push the update ASAP..