RTB (Real-Time Bidding)

Real-time bidding (RTB) is the auction process in which each ad impression is sold individually, in milliseconds, to the highest bidder. When a user opens an app, a bid request goes to buyers; DSPs respond with bids; and the exchange picks the winner before the ad loads.

RTB enables precise, impression-by-impression pricing based on the value of each user to each advertiser. It is the foundation of open-exchange programmatic buying and the main way a mobile DSP reaches in-app inventory at scale.

The speed of RTB means decisions are made by models rather than people, but people still set the rules: which goals to optimize, which supply to allow, which creative to use and how much to pay at most. The best results come from combining automated bidding with clear human strategy, regular reviews of source-level reporting and strict fraud filtering before every bid.