The total number of devices that first made payment. This can be an in-app payment, subscription, or custom payment (for example, an offline payment passed to MyTracker via the S2S API).
It shows how many devices have converted from being "non-paying" to "paying" during the chosen report period.
First time payers – Flow metric
First time payers CA – Current Attribution metric
First time payers LT – LifeTime metric
First time payers AT – Attribution Time metric
