I use CloudFlare's 1.1.1.1 DNS to mitigate my ISP tracking the domains I visit. They have an iPhone app too. I don't know enough about the space to say whether it's 100% effective.
Again, due to SNI tracking sites that one visits is possible even if DNS traffic is encrypted. At the very least one needs for the site to support ESNI or encrypted-site-name-identification.
But then in practice for ESNI to be effective one needs for the site to use CDN or similar solutions to ensure that there are a lot of sites for the given IP.
