The application is reading speed from GPS and change volume based on the selected template. This modifies system volume thus can be used with Music Player or any other music service as Spotify or Deezer.

After service is started volume is automatically set to 10%. While you exceed 30 km/h the application starts to modify the volume.

Muted standing template:
The volume is completely muted while you are at 0 km/h.
Volume shifts back to 100% while you reach 30 km/h.

City mode template:
Volume drops to 50% while your speed drops to 50 km/h.
Volume shifts back to 100% while you reach 75 km/h.

Custom template:
Hold CUSTOM button to enter configuration.
You can modify all parameters from previous templates as you wish.