Federal legislation aimed at eliminating loopholes that allow companies like Google and Apple track users using GPS location-based technology was proposed by Senators Al Franken, D-Minn., and Richard Blumenthal, D-Conn., on Wednesday. If signed into law, the Location Privacy Protection Act of 2011 could force companies to obtain explicit consent from smartphone users before gathering their personal data and would have to notify consumers on how that data is being used.