title: iPhone - Getting a reliable timestamp from the app to be store into external mysql database
body: <p>I want to write into a mysql database a timestamp in real milliseconds (I mean not just seconds x 1000). </p>
  
  <p>How may I achieve to get that timestamp into the app. I saw that some methods on NSDate could work, but they are based onto the iPhone date/time, that can be changed by the user, so using those methods would conclude to "fake" timestamps.</p>