Adbeat and Anstrex both get called "ad spy tools," but one maps enterprise display spend and the other rips native landers for affiliates; here's the honest head-to-head, plus where an open native-first index changes the math.
View-through attribution credits a conversion to an ad a user saw but never clicked, as long as it happens within a set window.
Viewability measures whether a served ad was actually in view, based on how much of it entered the screen and for how long.
An ad impression is a single instance of an ad being served and rendered on a page or app where a user could see it.
CPM (cost per mille) is the price an advertiser pays per one thousand ad impressions, regardless of whether anyone clicks.
