In the wake of the iCloud hack and revelations about government surveillance people have understandably never been more worried about their privacy, and presumably in part because of this Apple has created a new privacy page on its website, where it explains all its policies.
The page (opens in new tab) begins with an open letter from Tim Cook, where he outlines several key points including the fact that Apple won't build a profile on you to sell to advertisers.
The only part of Apple's business which relies on advertisers at all is iAd and that follows the same privacy principles as everything else, so it can't get information on you from Siri, iMessage, iCloud, Health and HomeKit, Maps or your call history.
He also claims that Apple has never worked with any government agency to create a backdoor into its products and services and never allowed any such agency access to its servers. He boldly goes on to say that the company also never will.
If that guarantee doesn't put you at ease there is some more detailed information on this if you dig deeper into the privacy page, including the fact that Apple can't bypass your passcode, so it can't feasibly respond to warrants that ask it to extract data from your device.
Apple can access your iCloud account but even then apparently less than 0.00385% of customers have had information disclosed due to government requests.
If you're more worried about hacking or information theft there's also a whole page dedicated to ways in which you can minimise the chance of that happening, though it's mostly obvious stuff like advising users to enable two-step verification and to choose a strong password and change it regularly.
It's worth a read in any case and while none of this is likely to totally alleviate privacy concerns it's certainly a step in the right direction.
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