The Allwinner H3 has excellent Linux support thanks to the open-source community. Armbian is a lightweight Linux distribution based on Debian or Ubuntu.
It is impossible to review this without mentioning the darker side. Because the H3 was the soul of budget tech, many generic firmware images came pre-loaded with adware, background data scrapers, or "phone home" services. Flashing a clean H3 firmware became a right of passage for tech enthusiasts; it was the digital equivalent of cleaning a thrift store find with bleach. Allwinner H3 Firmware