Apple unveiled its new mobile operating system, iOS 5, this Monday at the Worldwide Developer's Conference to much fanfare. But some are now saying that one of the OS's key new features, Wi-Fi Sync, which allows users to synchronize the contents of their music libraries without having to plug their devices into computers, was largely based on an app submitted to Apple months before.

Greg Hughes, a college student in the U.K., submitted an app called Wi-Fi Sync to the Apple Store in May 2010. The app let users access their iTunes libraries wirelessly, without docking a portable device to a computer, reports The Register. Sound familiar?

Hughes was rejected from the store, but not with a standard form email. Instead, an Apple rep personally called him to let him know that the app did not meet certain security standards and would not be allowed in. He also asked that Hughes send along a resume.

Undeterred, Hughes began to sell the app in the Cydia store, which peddles apps for jailbroken iPhones, at the price of $9.99 a pop. Since then, it's sold over 50,000 copies.

Apple's own Wi-Fi Sync feature, a part of the upcoming iOS 5 mobile system, not only performs the same function as Hughes' rejected app, but even has a strikingly similar logo (see here).

“Obviously I was fairly shocked,” Hughes told The Register. "I'd been selling my app with that name and icon for at least a year. Apple knew that, as I'd submitted it to them, so it was surprising to see that.”