The Android version should look and sound just as good as the desktop version. The APK is a smaller size because we compressed all the audio files to OGG instead of WAV, which is a lot smaller, and it sounds just as good. All our future games will be using OGG files on desktop as well. Most games do.
The images haven't been compressed any differently. They should look exactly the same.
As for JoiPlay, I'm not sure I can do anything about that, since it's a third-party tool, but if you're on Android, you should be able to play Benefitship with the APK at just as high a quality as on PC.