>> CPC ads on iOS cost $.40, while they are only $.18 on Android. However, with negative ROI, it would appear that Android ads are expensive at any price. No..

>> CPC ads on iOS cost $.40, while they are only $.18 on Android. However, with negative ROI, it would appear that Android ads are expensive at any price. No...they would be expensive at or above the price where ROI = $0. And ALL ads on Android don't have negative ROI, even if they do on average.