Facebook has added APIs for developers to access the home address and mobile numbers of users, so FarmVille can see where, as well as who, you are.
Permission to access such data must be given through the usual notification system, but with the vast majority of users simply agreeing with everything they're asked, the new facility is attracting privacy concerns beyond those incurred by sharing one's details with the developers of Bejeweled Blitz or similar.

Users almost always click "Allow" when faced with such decisions, as demonstrated by Microsoft's Active X technology more than a decade ago and proven by the thriving malware ecosystem sustained by inattentive Facebook users today. The alternative is pointed out by Sophos security, which suggests a more totalitarian approach: "Wouldn't it better if only app developers who had been approved by Facebook were allowed to gather this information?"

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