Guys what alternative is there admob ? What advise of these networks Mopub, Millennia Media, Inmobi, Mobclix, AppBrain, Appnext ? I apologize in advance for my English I am from Russia.
I have tried most of them. Fill rates was an issue for me. Admob gives best fill rates. But you must try them bcoz if cpm is good, low fill rates can also work for you.
This is why you use mediation. So the fillrate is always 100% but comprised of different ad networks.