Screenium is exclusively available at the Mac App Store.
A Mac with OS X 10.10 Yosemite, OS X 10.11 El Capitan, macOS 10.12 Sierra, macOS 10.13 High Sierra, macOS 10.14 Mojave, macOS 10.15 Catalina, macOS 11 Big Sur, macOS 12 Monterey or macOS 13 Ventura is required to use Screenium. Screenium is completely optimised for the new M1-based Macs.