IronFox is Firefox ESR-based, completely de-Googled, has zero telemetry, and comes pre-hardened for privacy.
IronFox is a fork of Divested Computing Group’s Mull Browser, based on Mozilla Firefox. Our goal is to continue the legacy of Mull by providing a free and open source, privacy and security-oriented web browser for daily use.
Version IronFox v140.0.4 released, .apk available for download here.
More discussion about the browser here.
Unfortunately, not available in FDroid yet.
I’ve been using it as my phone browser and have zero complaints.