[joewee]

One thing I found find suspect in iOS 13 is Apple automatically enables collection of data of your usage of 3rd party apps. Any idea what this is for?

[motohagiography]

Can't address authoritatively, but speculatively, there is reason to believe they would use device telemetry to check their platform exposure to malware.

It's a blanket excuse to say "security," but the only viable malware detection works by inventorying telemetry off-device, as on-device can be detected instrumented around by any advanced attacker.

[saagarjha]

Doesn't it ask you during the setup process whether you'd like to share analytics and usage data?

[joewee]

There is a per app sharing option. So perhaps they added granularity to what usage data sharing to exclude sensitive applications.