hexo It's mainly used to detect which networks have working internet access. It also detects captive portals and provides a prompt to deal with them using a dedicated OS captive portal handling app. The OS captive portal app enables handling captive portals without needing to disable an always-on VPN since the OS special cases it. GrapheneOS adds configuration for connectivity checks and you can disable them, but you'll lose the functionality of automatically switching to networks with working internet access, internet-dependent scheduled jobs waiting for working internet access and smooth captive portal handling. You'll need to handle captive portals by using a browser yourself in a profile without a VPN enabled without connectivity checks enabled. If you want to blend in with other users, then switch connectivity checks to Standard (Google) and combine that with a widely used VPN such as Mullvad so it's not obvious that you're a GrapheneOS user on the networks.