title: Multiple timers at once ios
body: <p>I am making an app where the user can have multiple timers going at once and see them in a list view.</p>
  
  <p>I am aware that there are 2 main options for working out time:</p>
  
  <ul>
  <li>Subtract the date started from current date (current date-start date)</li>
  </ul>
  
  <p><strong>OR</strong></p>
  
  <ul>
  <li>Use an NSTimer and take away 1 second every second from each active timer.</li>
  </ul>
  
  <p>I have previously been using the latter, but having looked around the internet I am starting to think that the data one may be better.</p>
  
  <p>Please could you let me know which you think is best to use, and if you chose the first one (dates), please could you provide some sample code on how to use it.</p>