Apple's iCloud cloud storage uses Google Cloud Platform to store data
According to Apple's updated documentation for iOS security (as of January of 2018), data stored by the company's iCloud service is currently stored on both
Amazon Simple Storage Service and
Google Cloud Platform servers.
Previously, Apple had a partnership with Microsoft that stored iCloud user data on Microsoft Azure servers, but references to this have been removed in the January 2018 security documentation for
iOS 11.
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