Horizontal scrollview pages 33% too small on iOS 7

Question

I have an app that contains a UIScrollView with 3 pages. It will swap pages when a over scrolls 50% over to the next element, and each page is an own UIViewController(And each of them contains UILabels and UITextFields). Each page has a width set equals the width of the current device.

This works perfectly on iOS 8, but the scrollview is 33% too small on iOS 7, and each view.frame.orgin.x is 33% too small, so the views overlaps. The width of each of the pages is, however, correct.

My question is, why is this offset by 33%? Why does this work perfectly on iOS 8, but not on iOS 7?

Original code for scrollview:

scrollview.contentSize = CGSizeMake((screenRect.size.width * 3), scrollview.frame.size.height);

Scrollview code that actually work:

CGRect screenRect = [[UIScreen mainScreen] bounds];
if([[[UIDevice currentDevice] systemVersion] floatValue] < 8.0)
{

    scrollview.contentSize = CGSizeMake((screenRect.size.width * 3) * 1.334, scrollview.frame.size.height);
}
else
{
    scrollview.contentSize = CGSizeMake((screenRect.size.width * 3), scrollview.frame.size.height);
}

Relevant code for each of the pages:

CGRect frame = [[UIScreen mainScreen] bounds];
if([[[UIDevice currentDevice] systemVersion] floatValue] < 8.0)
{
    frame.origin.x = (frame.size.width * page) * 1.334;
}
else
{
    frame.origin.x = (frame.size.width * page);
}
frame.orgin.y = 0;

Answer 1

My issue was that iOS 8 is different from iOS 7 when it comes to [[UIScreen mainScreen] bounds].

I found the answer to my issue here:

Is [UIScreen mainScreen].bounds.size becoming orientation-dependent in iOS8?