Of course, our reports will differentiate between events attributed to us and those that are not (AppsFlyer tells us in each postback). Getting all this information is very useful for several reasons:

If you are looking to acquire new users with mediasmart, we´ll make sure we do not impact those who have already downloaded your application.
Our algorithms can use the information from users that already have your application to find other similar users (look-alikes), considerably improving the performance of your campaign, especially during the learning period.
You will be able to get additional KPIs, such as Assisted Conversions
You will be able to measure INCREMENTAL METRICS

AppsFlyer - Measure Installs in Mobile Campaigns