Impressions are the number of times your application appears on the screen of someone browsing the application store, but there is something else. If the application scrolls on the screen, you get one impression. If the user scrolls the backup and your application reappears on the screen, nothing counts (since this will be a double count).
If the user clicks on the application bar while viewing the application store, you get a second impression. For example, imagine you are browsing an app store and scrolling through a page. Each application filling the on-screen presentation creates an impression. Suppose you understand that you just saw something interesting, and you scroll through the backup so that the application of interest makes the screen secret. This application (or any other application) does not receive a second impression of your action. But now you click on the application to see it in full screen. This action makes a second impression.
Now, if you install the application, then, obviously, this action is considered installation. So, in general, each application can receive no more than 2 impressions and one installation per session.
CoreyKat Mar 17 '15 at 17:07 2015-03-17 17:07
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