In-app bidding

In-app bidding brings the logic of header bidding to apps. Instead of asking networks one by one in a fixed order, the ad mediation platform sends a request to many bidders at once, and the highest bid wins. Every network gets a fair chance at every impression, and the developer is paid the real-time market price rather than a historical average.

It emerged in the late 2010s and became the norm for major mediation platforms. Bidders include large ad networks and, through exchanges, DSPs. Bids and requests often follow OpenRTB conventions, and the auction may run on the device or on the mediation platform's servers.

Benefits include higher revenue, less manual waterfall management and better transparency. Challenges include auction fairness when the mediation owner also bids, latency on slow connections, and supply transparency: app-ads.txt and sellers.json remain important for verifying who is really selling. In-app bidding also makes app inventory more accessible to programmatic buyers, and to fraudsters exploiting app spoofing.

Think of it like this

In-app bidding is like a live auction where all buyers raise paddles at once, instead of the auctioneer phoning each buyer one after another.

An example

A weather app in Canada receives bids from nine networks for a single interstitial slot within 300 milliseconds; the winning bid is a $9 eCPM, compared with the $6 its old waterfall would have filled.