A new report says iOS's share of the mobile ad market grew from 59% to 64% between May of last year and May, 2013, according to mobile ad firm Velti. Android's share slipped from 41% to 36% in 2013.
The iPhone 5's share grew by 7.4% over the year period, while the iPad added 3.7%.
Velti's report also notes that advertisers are ditching smaller display size ad units in favor of bigger ones.
Full screen interstitial, as well as 300 x 250 and 728 x 90 ads are all showing growth, while 320 x 50 ads on the iPhone specifically have seen a decline in usage.