i use DDG as my main search engine now and have for the last year and a half. i did use their browser on my iphone but it actually doesn't do a good job of blocking trackers. it blocks more trackers than safari but safari is better because you can use extensions.
i used this site to test:
Looking for an easy way to check the efficiency of your ad blocker?Toolz offers a simple and beautiful design test that allows you to quickly and easily test the performance of current ad/content blocker solution. Intuitive interface makes it easy to navigate and use, and the beautiful design...
d3ward.github.io
safari (no extension) = ~13% blocked
ddg = ~46% blocked
safari (w/ blockbear [free] extension) = ~65% blocked
safari (w/ wipr [paid] extension) = ~89% blocked
ddg on iOS doesn't seem to be affected by any extensions installed. i wish there was a way to download extensions for browsers like DDG. so that's why i will stick with Safari. also do we know what the DDG mac browser is built on? Please don't tell me chromium...
edit: they don't use chromium! they are basically using the safari engine. i wonder what they will do if they bring the browser to Windows. they should build it on Firefox.