In March, four Democratic U.S. Senators, Harry Reid, D-Utah, Chuck Schumer, D-N.Y., Frank Lautenberg, D-N.J., and Tom Udall, D-N.M., drafted a letter requesting that Apple, Google and Research in Motion (or RIM) eliminate the applications (user-friendly computer programs for specific tasks) on mobile communication devices that warn drivers of the locations of drunk-driving checkpoints.