Methods and systems are described for selecting an engaging ad campaign among advertising campaigns having different types of bid strategies. In one embodiment, an advertising system designed for selecting relevant and engaging ad campaigns for delivering to a device of a user includes an adaptive decision unit having filter logic for filtering eligible ad campaigns, a storage medium to store instructions of the system, and processing logic coupled to the storage medium. The processing logic is configured to execute the instructions of the system to receive and process an ad request from the device upon initiation of a software application on the device, filter eligible ad campaigns, convert each bid strategy of the filtered ad campaigns into an effective cost-per-mille (CPM) strategy, compare effective CPM strategies for the filtered ad campaigns, and select an ad campaign based on the comparison of the effective CPM strategies.