Working to unobtrusively add iAds in BS Weather

I'm starting to get excited about the prospect of finally releasing BS Weather to the U.S. iOS App Store!  One of the final steps is to integrate an ad network so that I can release the app for free to users.  The plan is to eventually add in-app purchases to the app to remove ads for a nominal fee.  I'm hoping the addition of an ad network will successfully offset the cost of the weather service.  I'm currently leaning towards Apple's iAds because AdMob ads are not allowed in apps deemed offensive by Google...which BS Weather certainly is.