Mobile/Platforms/Android
From MozillaWiki
Download Firefox for Android
Install Firefox from the Google Play Store
To find out more about Firefox for Android and other Mozilla mobile apps visit mozilla.com/mobile in your phone's web browser.
For direct APKs and pre-release versions visit https://github.com/mozilla-mobile/fenix/wiki#download
Support
If you have questions or trouble with Firefox for mobile, please see our dedicated Mobile Support site.