How does BookBub determine where and when my ads run?
BookBub Ads appear at the bottom of BookBub's emails. A real-time auction determines which ads are served at any given time. When you create a campaign, you decide which readers you want to target and how much you’re willing to pay for an impression (one opened email = one impression) or for a click from those audiences. When a reader opens an email, BookBub serves the ad of the highest bidder targeting that reader at that moment.