I lot of the hostnames or IP addresses that your android devices connect to without your direct knowledge or consent(1) are hard to find anything relevant about, except for the fact that Google owns a lot of the domains and IP ranges. This article helped me a lot when deciding which end points to block(2).

(1) You have given your consent, albeit unknowingly, since the EULAs are purposefully written so that the end user has a hard time understanding it.\
(2) In my case, with a systemless hosts file using Magisk and AdAway