This is not how iAd works, with iAd you implement an ad banner, and Apple encourages you to fill in content with which you have VERY limited control.
To do what you ask, I recommend you create your own ad, but not iAd. By doing this, you can do whatever you want (for a reason) when the user clicks on it.
Ref.
- (void)callUpAd { UIView *myAdSubView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 40)];
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