Samsung's Galaxy S4 powerhouse
According to SamMobile, the update that rides under Samsung's customized TouchWiz interface isn't so much of a visible change, but one that generally improves things under the hood.
With higher benchmark scores and faster speeds being reported, the Galaxy S4 should be a more finely-tuned device.
Outwardly, users may recognize touches such as generally sharper colors, UI tweaks, and changes to the keyboard and browser. Samsung is using the update to toss in a number of its own apps and services including Samsung Wallet and Samsung Knox for security.
Rounding things out are integrated support for the Galaxy Gear smartwatch, ANT+, and OpenGL 3.0.
Although the handset-maker has not provided an official changelog, the tech blog has rounded up a sizeable list of known adjustments. It's possible, however, that other small adjustments are tucked away neatly within the experience.
The Android 4.3 update should begin rolling out to various markets around the world and could take a few weeks to arrive. US owners, keep an ear on your respective carriers for update noise.