Launches are like visits but only for apps. This metric doesnt count just opening. It is being triggered when the app opens when no persisting launch is still running plus with a time limit of 5 minutes inactivity and visits with 30 minutes. Laucnhes get triggered automatically through the ios sdks and android you need to do an extra call but everything is automated.
In all help-articles it is shown to use Launches as metric for apps but when drilling down the data I am not able to use it like for pages like I would use it for visits as well. When creating a KPI Dahsboard using all the time launches and then also using visits for breakdownas this wont make the report consistent.
when you want to track how many times an app was open you need to create an own event which triggeres this beacuse launches are the wrong metric for that.