Here is a direct link to the website: http://atvlauncher.trekgonewild.de/index.php

This website will generate an apk that will show up on the Android TV home screen when installed. The great thing is is that it is really only a pointer to the actual sideloaded app. This means if you get an apk from the Play Store (not the Android TV Play Store) and sideload it it will continue to receive updates since it will remain unmodified.

Remember, this will also render the mouse feature with the right stick null. That feature only works on non-atv apps, so adding a launcher icon will no longer activate that feature.

If the UI won't work without a mouse on Android TV, this will actually break the app for you (unless you rock an actual mouse)