The zip file I eventually received from Apple was tiny, only 9 megabytes, compared to 243 MB from Google and 881 MB from Facebook. And there's not much there, because Apple says the information is primarily kept on your device, not its servers.USA Today: Apple took 8 days to give me the data it had collected on me. It was eye opening.
It's evident how much of your activity that Facebook logs when their file is 3x the size of Google's and almost 100x the size of Apple's.