Third Party Markets - Right Ad network

What is the better ad network for Third Party markets (slideme, soc.io, mobango, etc.) ? What I am looking for is ads that do not need Google Play Store to be installed on the end-user devices. As most of the ad networks are CPI and if the ads point to Play Store, it will lead to lack of downloads and hence no revenue. A side effect would be more frustrated users.

Are you guys aware of such ad networks?