Facebook is preparing a pair of major updates for its most popular iPhone applications, according to a source familiar with the apps. Facebook is testing an updated version of its main iPhone, iPad, and iPod touch client that integrates the social network’s powerful Graph Search tool. Graph Search is a feature that allows Facebook users to locate fellow users that have similar interests. For example, a Graph Search user can search for all friends who “Like” a certain Facebook page, musician, or movie. The upcoming app update incorporates Graph Search into the Facebook app’s main search bar.

In addition to the aforementioned update to the main Facebook for iOS application, Facebook is preparing a redesign of its Messenger app. Facebook is said to be internally testing two new versions of Messenger. The first version is said to look largely similar to the Messages application bundled into iOS. That version includes green interface elements. The second version in testing, which the source says is more likely to ship to end-users, is heavy on white space and very fitting for iOS 7’s design. It is not filled with blue interface elements like the new Facebook app. The new app has tabs for active/recent chats, contacts, and settings across the bottom…

Besides the fresh interface, the new Messenger for iPhone app will be able to integrate with the user’s iPhone contact list to find friends capable of being messaged via Facebook’s system. The new app also includes a redesigned Home screen icon that is a blue chat bubble with a white border. A similarly new version of Facebook Messenger for Android is also said to be in the works. Besides the new Facebook apps, Facebook is said to be testing several new video filters for upcoming versions of Instagram. It is currently unclear when Facebook intends to issue these updates, but all of these software enhancements are all currently in a “dogfooding” stage.

Last year, Facebook went on a hiring spree of Apple employees in a move to build faster, more robust software for iOS and its own Android-based Facebook Home software. One of Facebook’s most notable hires out of Cupertino was Greg Novick. He was the lead engineer in charge of re-building Facebook’s app. Before working at Facebook, Novick was one of the original designers of the original iPhone software and developed the first Phone and Mail apps to ship on the iPhone. According to several sources, Novick has departed Facebook and will return to Apple. Perhaps Novick is working on the interface for Apple’s upcoming wearables.

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