You just have to run littlesnitch, and see all the AWS servers that Apple applications hit. I don't think it's a secret that a ton of Apple applications are backended by AWS.
They're a massive company. When you already own telecom networks and run your own datacenters, selling cloud infrastructure services isn't too far fetched.
Apple discusses who it uses for cloud storage when discussing iCloud in their security guide (valid as of May 2016):
> The encrypted chunks of the file are stored, without any user-identifying information, using third-party storage services, such as Amazon S3 and Windows Azure.
Just for the record, our company has found that Amazon occasionally omits incidents from their status page, though I doubt they could get away with omitting something this significant.
All of the cloud providers have an incentive to downplay incidents and only post them to the status page when they're really bad. The bar is pretty high to get something on there.
I mean, they outline them in their fineprint. Amazon doesn't consider the unavailability of 1 EC2 availability zone an outage because their position is that you should be architecting around that. 2 or more AZ outages in the same region and it'll show up on their status page IIRC.
