title: Calculating elapsed time between two dates, gives different results in different devices
body: <p>Im trying to get the time elapsed from a specific date (in millis)</p>
  
  <p>In some devices I get the correct result
  however, in other devices I get wrong result</p>
  
  <p>here's the code that i use:</p>
  
  <pre><code>public static void timeElapsedFromDate(long workingDate) 
  {
      long diff = System.currentTimeMillis() - workingDate;
  
      long diffSeconds = diff / 1000;
      long diffMinutes = diffSeconds / 60;
      long diffHours = diffMinutes / 60;
      long diffDays = diffHours / 24;
      long diffWeeks = diffDays / 7;
      long diffMonth = diffDays / 30;
  }
  </code></pre>
  
  <p>Isn't it the way to measure time?</p>
  
  <p>thanks!</p>