In practice, we do not expect most customers to measure initial engagements directly, but to estimate them using readily available data. The most appropriate approach to use will depend on your game and your distribution platforms. Here are some examples of metrics that we recommend:
Number of units sold: For a game with an up-front payment, using the number of units sold is an acceptable estimate. Subtracting units where the end user requested a refund can make the estimate even more accurate.
First-time user download: For a game with no up-front payment, distributors often provide the number of distinct user accounts that downloaded a game for the first time. This is also an acceptable estimate, it is an event that typically occurs only once for each end user.
This list is not comprehensive, but submitting an estimate based on any of these metrics will be acceptable. We plan to provide more specific guidance on how you can find these numbers in publisher dashboards for the major distribution platforms. We are also happy to work with you to identify the best way to approach estimating initial engagements for your game.