The latest batch appeared this week on Sina Weibo, the Chinese microblogging platform; the screenshots were later certified legit by Mark Gurman of 9 to 5 Mac, who spoke with a few Apple insiders.
You can take a look here.
Just don't be expecting a major overhaul from iOS 7. For the most part, if this is indeed iOS 8, the next Apple mobile OS will greatly resemble the last Apple mobile OS, from the "flat" icons to the Helvetica Neue font. Which is not to say there are no changes. Among the apps included in the screenshots are TextEdit and Preview, along with something called Tips.
TextEdit, presumably, is a basic word processor in the mould of the Mac software; Preview looks like it will mirror the image/PDF/file viewer already available on Apple's desktop operating system. As for Tips, Craig Lloyd of Gotta Be Mobile says the app is "probably just a digital and interactive version of the user manual that comes with every iOS device."
But the feature that's garnered the most attention is Healthbook, a fitness app that Apple is reportedly hoping to make a flagship feature on its new mobile OS.
In related news, Apple has rolled out iOS 7.1, the first major update to iOS 7. The update includes upgraded fingerprint recognition for the iPhone 5S, a fix for a persistent home-screen bug, improvements to iTunes Radio, and a feature called CarPlay, which helps integrate messaging, maps, and music with your vehicle's touch screen.