By Slash Lane

Published: 08:20 PM EST (05:20 PM PST)

Apple's iPhone OS 4 could sport built-in integration with Facebook, including contact syncing and social connectivity to App Store software, according to a new report.

Citing a "plugged-in source in the mobile industry," Silicon Alley Insider reported Wednesday that the forthcoming iPhone software upgrade will "at least" allow direct syncing with Facebook contacts. The report said the feature could be unveiled as soon as June 7, at the keynote address at Apple's annual Worldwide Developers Conference.

"We also hear that Apple could be integrating Facebook Connect directly into its software developers kit so programmers can more easily add Facebook 'social' features to their apps," author Dan Frommer wrote. "But we don't have details on how that might work."

He also speculated that Apple could build "some sort of Facebook messaging features" into the latest version of the iPhone OS, such as allowing messages to be sent via Facebook Chat in a manner as simple as sending a text message.

Integration with Facebook is already a prominent feature of Google's competing mobile operating system, Android 2.0, released last year. Microsoft has also planned strong Facebook connectivity with its forthcoming Windows Phone 7, due out later this year.

In early April, Apple introduced iPhone OS 4 with 100 new features, the largest of them multitasking support for the mobile operating system. Developers currently have access to preview builds of iPhone OS 4, but the software does not currently offer any integration with Facebook.