I was quite pleased to hear a CEO of the Vivaldi company talk about owning a Cosmo and Gemini at 15:30 here:
https://www.youtube.com/watch?v=zhkkFcEwCBoThey just released a stable version for Android and it is optimized for landscape mode, apparently, as mentioned in the video. It beats Chrome and other browsers by a large margin (and can sync with a desktop version, though that is just a bit buggy but useful enough). I wholly recommend both on desktop and especially on your phone!