Contactive acts and feels like an extension of the contacts or address book that exists within native Android 4.0. When you receive a call from a friend, Contactive will also pull up the caller's most recent online activity.
By default, Android's own native People app touches upon social network updates, but only within Google+ vs. Contactive's wider cast of Facebook, Twitter, Foursquare, and more. The philosophy behind displaying a caller's activity on the Incoming Call screen is to act as a kind of "cheat sheet" for conversation topics before answering the call.
Having an elegantly miniaturized news feed being displayed does indeed offer some convenience, but it's not without its flaws. Because Contactive relies on its own global directory, in addition to the standard Web services like Facebook, LinkedIn, Twitter, etc., its effectiveness is dependent on just how much information you share with the application.
The app, itself, also requires you to register an account with an e-mail and password, likely for identifying unknown callers. Contactive already aggregates information from a wide variety of publicly available sources, which can save you the trouble of verifying a caller's identity should they attempt to falsely represent a group.
Contactive is available for free from the Google Play Store.