HelloHello!
I can recommend HilltopAds. We have a lot of positive experience with Apps and a lot of converting mobile traffic for it. Also, you can target ads on specific devices, OS, mobile carriers. Simply speaking, you can optimize your ads as you wish
Feel free to ping our affiliate manager Helga via Skype. Her ID is OK HilltopAds.
Cheers!
Kindly accept me on Skype.
Looking for business partnership with you.