Ad Request: The request made to an ad server to display an advertisement. The request doesn’t always result in an ad displayed, for a variety of reasons, including mobile network latency.

Impression: When an ad is shown, regardless of whether it is viewed or clicked.

Fill: The number of ads received. The number of Fills is always equal to or less than the number of Requests.

Fillrate: The percent rate at which ads are received. Calculated by the formula (FILLS / REQUESTS) * 100

CTR (click-through rate): The ratio of number of clicks per ad to the number of total impressions, as a percentage rate. Calculated by the formula (CLICKS / IMPRESSIONS) * 100

DAU (daily active users): The number of unique users of the application, per day.

Display Rate: An indicator that reveals how many of the downloaded or received ads were shown. Calculated by the formula (IMPRESSIONS / FILLS) * 100. A lower display rate means ad networks are negatively affected, and eCPM can drop. A low display rate is caused by the caching or logic of ad impressions.

ARPDAU: The income indicator from one user of the application per day. Used to compare returns. Calculated by the formula REVENUE / DAU.

Banner refresh period: Amount of time between banners being updated or refreshed.

Bundle ID (package name): Unique identifier of the application in the store.

Cache: Uploaded or received ads that have not been shown yet.

Auto Cache: A mechanism through which ads will be loaded automatically without manual requests from the developer side.