Windows Phone 7 offers Facebook integration right out of the box with its People Hub. But that is merely Facebook information being pulled into the WP7 interface. The official Facebook app on WP7 offers the true Facebook experience. It's a simple-to-navigate app with a main screen that lists all the familiar Facebook pages such as messages, news feed, profile, photos, places, friends etc., with additional screens for "top news" (equivalent of news feed), recently posted photos, events like parties and friends' birthdays, and notifications.

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