title: Sign In with Apple: How to achieve it for existing app?
body: <p>With recent major updates released by Apple on 3rd June 2019, there is one feature <a href="https://developer.apple.com/sign-in-with-apple/get-started/" rel="noreferrer">Sign In with Apple</a>. Information about 'how to use this' in app is available but I can see any sample source code, how to achieve this feature in your existing iOS app.</p>
  
  <p>I'm looking for a sample source code, as I can't understand how to start with this.</p>
  
  <p>And what I've tried: <a href="https://developer.apple.com/sign-in-with-apple/get-started/" rel="noreferrer">Sign In with Apple</a></p>