I have written an iPhone and iPad universal app which runs fine in the iPad simulator on Xcode, but I would now like to test the iPhone functionality. I seem unable to run the iPhone simulator with this code as it always defaults to the iPad?

Instead I tried to run on the device and as it begins to run I get the following error:

dyld: Symbol not found: _OBJC_CLASS_$_UISplitViewController
  Referenced from: /var/mobile/Applications/9770ACFA-0B88-41D4-AF56-77B66B324640/Test.app/Test
  Expected in: /System/Library/Frameworks/UIKit.framework/UIKit in /var/mobile/Applications/9770ACFA-0B88-41D4-AF56-77B66B324640/Test.app/TEST

As the App is built programmatically rather than using XIB's, I've split the 2 device logics using the following lines in the main.m method:

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    retVal = UIApplicationMain(argc, argv, nil, @"AppDelegate_Pad");
}
else
{
    retVal = UIApplicationMain(argc, argv, nil, @"AppDelegate_Phone");
}

From that point forth they use different AppDelegates and I've checked my headers to ensure the UISplitView is never used nor imported via the Phone logic.

How do I avoid this error and is there a better way to split the universal logic paths in this programmatically-created app?