iAd is a native extension that enables iAds capabilities on iOS. The extension allows the banner to be displayed at the top of at the bottom of the screen. Additionally there are several events fired by the SDK that can be monitored (such as when an ad is loaded).

Sample

AdBanner.adView.startShowingAds(AdBannerPosition.TOP,false);
 AdBanner.adView.addEventListener(AdBannerEvent.AD_LOADED,function(e:AdBannerEvent):void{
         trace("Ad Loaded");
         AdBanner.adView.visible = true;
         trace("leaving: " + e.leaving);
 });
 AdBanner.adView.addEventListener(AdBannerEvent.AD_LOADING_FAILED,function(e:AdBannerEvent):void{
         trace("Loaded Failded: " + e.errorCode);
         AdBanner.adView.visible = false;
 });
 AdBanner.adView.addEventListener(AdBannerEvent.USER_INTERACTION_STARTING,function(e:AdBannerEvent):void{
         trace("Starting");trace(st.orientation);
 });
 AdBanner.adView.addEventListener(AdBannerEvent.USER_INTERACTION_FINISHED,function(e:AdBannerEvent):void{
         trace("Finished");trace(st.orientation);
 });