title: iOS - open photo from photo album in my app
body: <p>I would like to let users browse photos in their photo albums, tap the action button, and share/open selected photos in my app. Some apps (like Viber and WeChat) provide a custom view to handle this. This is the WeChat screen:</p>
  
  <p><img src="https://i.stack.imgur.com/s2R7s.png" alt="enter image description here"></p>
  
  <p>What is the name of this feature and which class do I have to use to achieve this behavior?</p>