URL not opening on device yet it opens in Xcode

I have a simple TabBar app which contains a button. Pressing the button opens a URL when running the app in the Simulator.

EDIT: The app runs in both iPhone & iPad simulators (ver 5.1). It also works when downloaded onto an iPhone (iOS 5.1.1)

But when I run the app on an iPad - whether it is tethered to Xcode or standalone - the URL does not open. In fact the breakpoint set in the event handler is never reached.

Xcode ver 4.4

iOS 5.1.1

It seems like the button containing the URL is not connected to an event handler in the storyboard. Yet I have double-checked it.

Any suggestions are welcome.

Solution

I found the problem. I had created a clear button which I laid over a UILabel. Clicking the button opens the URL. However, I did not have the struts configured the same for both objects. So when I rotated the device the button no longer aligned with the UILabel. Hence, I could press on the UILabel but nothing would happen. It was not an issue on the iPhone, because the app does not support rotation on that device. Thanks for your input.