Every build covered on astuteserverbeta.com is tested on real phones before its download information is published. Niklas Hoffmann installs the build himself, plays the test sessions the way a beta tester would, and only then is the version listed with its file size and compatibility details.
Each review works through the same set of checks, in the same order, so versions can be compared fairly. The build is installed cleanly from its APK file, the permissions it requests are reviewed, performance and battery behaviour are checked during normal play, and the file goes through a safety scan. When a new version lands, the checks are run again before the listing is updated.