First screenshots of Android 4.3 running on a Galaxy S4 emerged online. This is actually the stock Android build for the Galaxy S4 Google Edition and not the official Android 4.3 by Samsung with Nature UX. There are no visible changes at a glance, apart from the updated camera interface.
Android 4.3 will probably be the last Jelly Bean build. Google will publish this update and move on to releasing Android Key Lime Pie 5.0 in the autumn.
Owners of Galaxy S4 and HTC One, as well as the Xperia Z and Huawei Ascend P6 in the near future, will be able to flash the Google Edition firmwares on their devices if they so desire. It’s still non-legitimate and will require rooting, breaking your warranty and other inconveniences, but nothing you can’t work out over a free afternoon.Source: GSMArena