Comment by anderskaseorg

DoT is DNS over TLS: https://techdocs.akamai.com/etp/docs/configure-dot-doh, https://www.cloudflare.com/learning/dns/dns-over-tls/, https://developers.google.com/speed/public-dns/docs/dns-over..., https://en.wikipedia.org/wiki/DNS_over_TLS

Android ≥ 9 natively supports DNS over TLS: https://android-developers.googleblog.com/2018/04/dns-over-t...

So does iOS ≥ 14: https://developer.apple.com/documentation/networkextension/d..., https://support.quad9.net/hc/en-us/articles/360057889591-Set...

The link you’re referring to, https://github.com/celzero/rethink-app, supports DNS over Tor, but does not call it “DoT”. It does not support DNS over TLS (https://github.com/celzero/rethink-app/issues/441), and it is not something that phones have built-in.