title: Horizontal scrolling with parallax background for ios
body: <p>I'm facing a challenge of creating an introduction view, something like the "Cleanio" app (<a href="https://itunes.apple.com/fr/app/cleanio-pressing-la-demande/id885856031?mt=8" rel="noreferrer">https://itunes.apple.com/fr/app/cleanio-pressing-la-demande/id885856031?mt=8</a>).<br/>
  Here is how it looks like:<br/>
  <img src="https://i.stack.imgur.com/SK2Jk.png" alt="enter image description here">
  <img src="https://i.stack.imgur.com/7fSUm.png" alt="enter image description here">
  <img src="https://i.stack.imgur.com/GmJcS.png" alt="enter image description here"></p>
  
  <p><br/>
  So, the background and the overlay are moving independently and not in the same speed.<br/>
  Does anyone have a start point how to realize that?</p>