LibreWolf is a great privacy oriented Browser for desktop. But there is no version for android or IOS . There are some like mull but they have their own problems. Mobile phones stay with us most of the day. So we need extra privacy for it.
Avoid Gecko-based browsers like Firefox as they’re currently much more vulnerable to exploitation and inherently add a huge amount of attack surface. Gecko doesn’t have a WebView implementation (GeckoView is not a WebView implementation), so it has to be used alongside the Chromium-based WebView rather than instead of Chromium, which means having the remote attack surface of two separate browser engines instead of only one. Firefox / Gecko also bypass or cripple a fair bit of the upstream and GrapheneOS hardening work for apps. Worst of all, Firefox does not have internal sandboxing on Android.
https://grapheneos.org/usage#web-browsing
That sounds like the exposed attack surface is a lot more than just whatever sites are running under your Firefox process.
But what do I know, I’m not a developer of security-hardened Android forks, so I just have to pick which randos on the internet I choose to believe. When the developers of DivestOS and GrapheneOS both have lengthy write-ups on why chromium base browsers are significantly more secure, I’m going to believe them because I don’t have the low level technical knowledge to refute what they’re saying.