https://www.cnet.com/news/apple-moving-icloud-encryption-keys-to-china-for-china-based-users/

Apple has privacy advocates worried over a change in how it protects the data of iCloud users in China, according to a pair of reports.

The data, such as messages, emails and photos, is shielded from prying eyes by encryption, which means it's coded. But Apple will begin storing the keys for the code not in the US, as it's done till now, but in China, say reports this week by Reuters and The Wall Street Journal.