My Results with Various Ad Networks: Revmob, Admob, iAd, Adcolony, Chartboost, AppLovin, AppFlurry and PlayHaven / Upsight, StartApp

Generating revenue from free applications is difficult. One great way to do this, aside from In App Purchases, is advertising. Advertising not only helps to generate revenue directly, but it can also serve as a constant reminder for your users that they should upgrade to a paid version of your app. The annoyance should be