# Calculating an App's Unique Users

DT uses the app start event to count the app's unique users. When looking at a daily aggregation, this represents that app's DAU (daily active users).

DT uses the app's unique users to reflect in our reporting system with the following metrics:

| METRIC                                 | DESCRIPTION                                                                                                                                                                           |
| -------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Publisher App Unique Users             | The publisher app's unique active users. This metric is accurate only when a publisher initializes our SDK on app start! When splitting by day, it shows the daily active users (DAU) |
| Publisher ARPDAU                       | <p>Publisher's average revenue per daily active users. <br><strong>This metric is accurate only when a publisher initializes our SDK on app start.</strong></p>                       |
| OFW Engagement Rate                    | DT Offer Wall's daily engaging users divided by the publisher app's daily active users.                                                                                               |
| Offer Impressions per App Unique Users | Offer impressions divided by app unique users                                                                                                                                         |
| OFW Impressions per App Unique Users   | OFW impressions divided by app unique users                                                                                                                                           |

## Clarifications

* DT displays the unique users who opened the app during a chosen period of time and does not count duplicates (e.g., if timeframe = month, we show MAU).
* If DT identifies the same user from different countries (due to proximity), at the country level it appears twice; on a worldwide level we count it once.
* DT bases the count on the user game if provided. If not, DT counts based on device ID.

{% hint style="warning" %}
These metrics are accurate only if a publisher initializes our SDK on app start!
{% endhint %}