Yes! Please help! I have exactly the same "problem".
We are serving different Ads in different zones for different screen resolutions...
For Example:
448x1080; 1024x90; 448x1080 Wallpaper -> Desktop
960x250 Wallpaper Fallback Tablet -> Tablet
320x250 Wallpaper Fallback Smartphone -> Smartphone
So if a user is on Desktop he make a Impression for ALL of them! But i just want that the user add an impression to the zone of what he is seeing...
Please help!!!