title: How to use SF Symbols in iOS 12 and below?
body: <p>I am updating the icons in my app. After I heard Apple released an icon font named <code>SF Symbols</code> with iOS 13, I was wondering if I can only use them in iOS 13 or if it is possible to use them in lower versions of iOS too.</p>
  
  <p>If I want to use them, do I have to implement a fallback for older versions?</p>