Glossary
What is Mediation?
Also called: app mediation, mediation platform, ad mediation
Mediation is the layer in an app that decides which ad network fills each ad, using a waterfall, a bidding auction or a mix of both.
हिंदी में पढ़ेंMost apps work with several ad networks. A mediation platform is the SDK that sits between the app and those networks and runs the auction for each ad. Networks plug in through adapters, so one platform can call many sources.
Mediation can run as a waterfall, calling networks one by one in order of the average eCPM you set, or through in-app bidding, where sources bid at once. Google AdMob mixes bidding and waterfall sources in one mediation group. AppLovin MAX runs a unified first-price auction and merges bids with your waterfall. Unity LevelPlay runs a hybrid of bidding and non-bidding sources. These three reportedly run most app mediation.
Their demand also plugs into each other: LevelPlay lists AdMob and AppLovin among its networks. So the usual setup is one mediation platform per ad unit, with other networks added through adapters. Putting two platforms on one ad unit splits the bids between them.
Example
In one AdMob mediation group, Network A bids $4.10 and Network B bids $3.60 in the bidding auction, and waterfall Network C has an average eCPM of $3.90. A wins the auction and is slotted above C, so A gets the first chance to serve at $4.10. B lost and is not called again.
Why it matters to publishers
Your mediation setup decides which buyers ever see your impressions. Finding which SDK makes each ad unit's show-ad call is the first step to fixing gaps.