How ad mediation works
An app that earns money from ads can connect to many ad networks, but integrating and managing each one separately is slow and error-prone. A mediation platform solves this with one SDK in the app. When the app needs an ad, the mediation layer requests one from connected networks and serves the best result.
The goal is to maximize revenue per impression while keeping fill rate high:
ad revenue = ad requests x fill rate x eCPM / 1,000
A worked example: a game makes 3,000,000 ad requests a day. With one network, fill rate is 80% at a $2.00 eCPM, so daily revenue is 3,000,000 x 0.80 x 2.00 / 1,000 = $4,800. With mediation across several networks, fill rises to 97% and eCPM to $2.40, so revenue becomes $6,984, a 45% lift from the same users and the same ad slots.
Waterfalls and bidding
Waterfall mediation ranks networks by expected eCPM and calls them in order, each with a price floor. It is predictable but needs constant tuning, and a network lower in the list may have been willing to pay more for a given impression.
In-app bidding sends each impression to all bidding networks at once and takes the highest bid. It usually raises eCPM and reduces manual work. Many apps run a hybrid: bidding networks compete first, with a waterfall behind them for networks that do not bid.
What to watch
- eCPM by network and format: where value comes from.
- Fill rate: how often a request gets an ad.
- Latency: slow ads hurt user experience and retention.
- Impressions per user: more ads raise short-term revenue but can lower retention.
- Ad quality: misleading or broken ads damage trust and store ratings.
Mediation and user acquisition
For ad-supported apps, mediation data is half of the ROAS picture: it says what users earn from ads, while the MMP says which campaign acquired them. Linkrunner does not import ad mediation or impression-level ad revenue today; it attributes installs, in-app events, purchases and subscription revenue to campaigns. Teams that need ad revenue by campaign join their mediation reports with Linkrunner's install data through exports and APIs.