title: How to display an image only the first time an app is opened?
body: <p>I'm writing a very simple app and I would like to display a message the first time an app is opened. And not display after that at all.</p>
  
  <p>The message will be on an image.</p>
  
  <p>Is there any way to do this? I'm using swift code and would really appreciate some help. </p>