Disconnect Pro for iOS is also a great tool. Hasn't failed me yet and makes adding custom trackers super easy via the list of recent connections. I blocked 30.8k trackers and saved 3 GB of data last month. :)

it's not a proper solution (apps can simply communicate with their servers public ip instead of looking up a domain name.)

If that becomes more widespread, I would expect a future generation of blocking software to start use ASN information.

On IOS apple only allows (some) dns based blocking afaik

Wouldn't that loophole work on all DNS-based blockers/black-holes on any platform, namely Pi-hole (and the hosts file for that matter)?

Yes. I use a DNSBL in my router (pfBlockerNG), and I've been considering writing a small script to resolve every IP in the blocklist and then block outgoing connections to those IPs.

Of course this is only useful at home. As soon as my phone leaves the house, everything is open again.

Ooh, good idea. Would probably only have to write ~1 time per day to a separate, parallel list. Or have a small VPS do the work continuously and push changes to a Git repo so others can pull it however often they want.

I’d love to take a look if you end up doing that!