In a nutshell: MAU = Monthly Active Users.
Every time your mobile app gets installed, we generate a new unique ID for the app on the user device. This ID is passed to our servers once we receive a request for translations from the installed application. If this ID wasn’t previously registered during the current month, then we increment your MAU counter by one.
In other words, the counter is increment the first time the ID is seen in the current month. If that ID was already registered (seen by our system), your MAU counter won’t be incremented.
At the beginning of each month the MAU counter will be automatically reset.
If your QA team does a lot of testing, and the app is getting installed/uninstalled many times as the new builds arrive, then each new app installation will increment the counter.
Once your MAU reaches 90% we will give you a warning:
Once your MAU goes over 100% then we will show you an error and your users won't be able to download new translations from us: