I have a UIScrollView inside another UIScrollView. For example:

This grey area is my device.
Red scrollview is in the background
Yellow scrollview is a subview in red scrollview.
What i want to do is scroll up and down and still have an option to scroll right/left. But when i set delegate to yellow scroll view i cant move right/left. How to handle this ?
It is very easy, you just have to check which scrollView you are using to call the delegate method.
In your delegate method:(your delegate method receives a parameter UIScrollView *)scrollView
This is how you control 2 scrollViews with one delegate method.
About what you want to do:
It more be more useful to only make 1 scrollView and set its properties so you scroll to left and right and up and down, two scrollviews are useless and the fact, that they overlay is a problem because the scrollview underneath can not be accessed.