AOL’s (NYSE: TWX) Platform-A is trying to entice developers to make apps that carry its ads by promising guaranteed rates for CPMs on Facebook and Bebo, which AOL bought for $850 million back in March. AOL isn’t disclosing the amount of the guarantee but, on average, CPMs on remnant networks tend to be around the 10-cent range and often less; one source told paidContent that AOL’s guarantee will be around 40 cents. So for some developers, it could add up. The guaranteed CPM rates will apply to the first three impressions for each unique U.S. visitor who visits an approved developer’s application.