Source on GitHub
Testing and Issues
You can test this app and submit issues during the testing period of the Android Contest 2021, Round 2 contest.
Entries with serious issues will not be able to win the contest, but even minor issues might be important for overall results.
If 3 dots in Background Controls activity does nothing on click - click it again, the first click could be delayed a bit.
[Also, the APK is arm7 only, but can be installed on arm64 devices as well]