blockerDNS: Ad Blocking for Any Device... Without an App, VPN or Proxy!

I used to block ads on mobile using my own VPN that pointed to custom DNS servers I maintained. But when Android 9 was released last year with its new "Private DNS" setting that let you set your own DNS server without rooting (DNS-over-TLS, specifically) I was intrigued. One thing led to another and eventually I had my own DNS-over-TLS implementation running successfully. It was great. It didn't have the overhead of running one of the typical ad-blocking schemes like VPNs, separate browsers with DNS settings changed, or convoluted proxies. I just entered my URL into the Private DNS setting and that was it. It was so easy and efficient that I thought I'd whip up a little subscription service!