@bert_hubert @jornane @mysk I use OS uptime to make caches behave correctly regardless of system clock changes.
iOS inherited a lot of from the Mac which grew up in more innocent times. The Address Book API is a good example. On the Mac it didn't matter that any app could do what it liked. On iOS within 3 or 4 years apps were abusing it which lead to changes on both platforms.
As it happens the uptime APIs are seeing more scrutiny at the moment:
https://developer.apple.com/news/?id=z6fu1dcu
https://developer.apple.com/documentation/bundleresources/privacy_manifest_files/describing_use_of_required_reason_api#4278394
@andrewtj @bert_hubert @mysk Users don’t change the system clock that often in my experience. Why do you need to be robust against that? Especially since they can reboot their devices, which then also messes with your cache.