Sammobile has reported that they have had trialed a leaked firmware of Android Jelly Bean 4.3 update for Samsung Galaxy S4.
The reported leak is named I9505XXUEMJ3 and is reported to be the final version prior to release; a Golden Master, if you will. This means no further features will be added other than any reported bugs by alpha and beta testers prior to release.
Now, it’s believed that 4.3 could be release for Galaxy S4 within the next couple of weeks by Samsung, however, it is also reported that some of the flagship models will be automatically updated to 4.4 Kit Kat soon after it launches (which could be as soon as October 15th, according to some reports).
So far, the report is that 4.3 update for Samsung Galaxy S4 is a stable release, and there are no new major features.