Facebook is experimenting with technology that tracks cursor activity while on the site. The technology can tell where a user is hovering his or her cursor, meaning it might be used to determine the best location to place an ad. The technology also tracks whether mobile users can see their News Feed at any particular time from their phone. Facebook made the following statement:
These experiments look at aggregate trends of how people interact with the site to inform future product decisions. We do not share this information with anyone outside of Facebook and we are not using this information to target ads.
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