title: Moving an image with ios 7 parallax effect
body: <p>I just saw Facebook's new paper app that makes images move based on the parallax effect. So it zoom's the image to full screen and when you tilt the screen, it scrolls the image to the side you tilted. I have been able to add the parallax effect like apple has it, but not like how facebook has it. Does anyone have any ideas how they did this. Here is the basic code I was using for parallax:</p>
  
  <pre><code>UIInterpolatingMotionEffect *interpolationHorizontal = [[UIInterpolatingMotionEffect alloc]initWithKeyPath:@"center.x" type:UIInterpolatingMotionEffectTypeTiltAlongHorizontalAxis];
  interpolationHorizontal.minimumRelativeValue = @-10.0;
  interpolationHorizontal.maximumRelativeValue = @10.0;
  
  UIInterpolatingMotionEffect *interpolationVertical = [[UIInterpolatingMotionEffect alloc]initWithKeyPath:@"center.y" type:UIInterpolatingMotionEffectTypeTiltAlongVerticalAxis];
  interpolationVertical.minimumRelativeValue = @-10.0;
  interpolationVertical.maximumRelativeValue = @10.0;
  
  [self.backgroundView addMotionEffect:interpolationHorizontal];
  [self.backgroundView addMotionEffect:interpolationVertical];
  </code></pre>