I've always thought if I owned any sort of fund, I would immediately have made basically this when I first saw pi-hole and then analyzed the data to estimate a given tech companies DAU numbers. I wonder who owns NextDNS. No idea if my idea would work or be per se legal but I bet you can grab some interesting insights.

i've used some of those as well, and finally settled on adguard pro for my ios devices. do you (or anyone else) know how nextdns and adgaurd compare on ios?

adguard pro allows customization of dns servers (including DoT), has a running local log of dns queries, and provides custom whitelists/blacklists functionality. their dns (or maybe the app) very occasionally hangs requests, making my device seem like it's disconnected.

i've considered switching to nextdns but haven't found a compelling reason yet.

The only annoying part is that it doesn’t give you any sys notification when blocking a site. You have to check the logs. So if gmail isn’t losing the inbox that means something needs to be whitelisted and you now have to dig.