the documentation for DeviceActivityCentre.startMonitoring ( https://developer.apple.com/documentation/deviceactivity/deviceactivitycenter/startmonitoring(_:during:events😃 ) seems to suggest there is a limit to how many different events one could limit for ( "To avoid errors, reduce the number of unique, tightly-scheduled activities. ") - what are these limits?
Given that it looks like the reported events are per DeviceActivityEvent.Name it seems mostly likely an app would need to create an event for every app/web domain it wanted to monitor to be able to get stats on how much time was spent in each. - ie. there doesnt seem to be a way to extract stats, rather just collect them.
