Octoprint “using Google's DNS server” octoprint seems to have a setting that involves googles DNS server.

my question is is that server used to access octoprint over the internet via printoid "android app" or via browser? if not then what does it mean?
The program is pinging that address to check the internet connection to "prevent resource intensive operations if it's already clear that they won't succeed anyhow".  It checks for connectivity, if it has it then it will check for update otherwise it won't check for an update.