Android application package of Dangbei Desktop, a launcher for TV boxes and smart TVs, version 4.1.6, labelled in the name as a cleaned or purified build. At 18.5 MB it installs as a standard APK by sideloading through a file manager or ADB once installs from unknown sources are allowed. Technicians sometimes swap the stock home screen of a set-top box with such a launcher after a reflash. Because it is a modified build from an unofficial source, scan it first and test on a device whose original firmware is backed up.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @tv_software. Enginerys does not host this file.