title: How to use new San Francisco font in iOS 9?
body: <p>Before <strong>iOS 9</strong> to reference fonts we used <code>fontWithName</code> of <code>UIFont</code>:</p>
  
  <pre><code>[UIFont fontWithName:@"HelveticaNeue" size:18]
  </code></pre>
  
  <p>Now we're moving to iOS 9. How to reference a new <strong>San Francisco font</strong> in the same way?</p>
  
  <p>We can use it with <code>systemFontOfSize</code> of <code>UIFont</code>, but how to reference styles other than regular? For example, how to use <strong>San Francisco Medium</strong> or <strong>San Francisco Light</strong> fonts?</p>