I wonder how they get around GDPR. Normally I'd expect the EU to dish out a pretty hefty fine for this sort of thing, but something tells me Apple lawyers and penpushers has been busy making sure this passes, even though it's technically illegal.
It all lives on your device in order to make it work better. Apple literally doesn’t have custody of the data so it’s not relevant to the GDPR. It’s your data.
For the GDPR to have impact here, wouldn't they have to be collecting the information in the first place? If they're doing all the work on your own computer, that wouldn't trigger any GDPR issues.
If it is stored entirely on the machine you own, then you are processing and storing the data.