Cost represents the total amount spent on customer taps or clicks over the time period covered in the report. It reflects the cumulative cost of each interaction with your app ad, whether that leads to an impression, download, or other event. Tracking cost allows understanding the return on investment of your campaign budget and verifying funds are being allocated efficiently. The cost metric shows how much is spent in the aggregate to generate various outcomes like new users or re-engagement of existing customers. It is a key factor in optimizing ad performance and ensuring marketing initiatives are profitable.