The use-case is the exact same one that is on a desktop. System-wide setting for a comfortable max volume, application specific volume because different apps handle audio differently. Youtube videos are loud, voice chat is usually moderate, some recordings are quiet.

An example I can think of is when you're listening to a podcast or music that has been recorded on low volume. Without a volume mixer you're forced to increase the general volume, resulting in overly 'loud' sound notifications from other apps.

Media volume and notification volume have their own sliders

The media volume slider is joint across the apps though if they aren't notifications.

Unfortunately this doesn't work for notifications such as 'lap times' from the Garmin app. This is also considered media by the phone.

That can be fixed with Garmin notification sound being treated as a notification sound.

Adding per app volume control is IMHO a really bad UX. It means there's a master volume and then per app volume is like a coefficient the app volume is multiplied by.

My car has its own volume control separate from the phone bluetooth volume and I hate the experience of having two volume knobs interacting with each other when all I want to do is to increase or decrese volume

> Adding per app volume control is IMHO a really bad UX.

I really prefer it for having different things set at different volumes. Like presets.

Samsung phones have this, and I use this to play music at a pleasant low volume while watching YouTube videos at a higher volume.

I'm surprised Pixels don't; small things like this area each QoL wins.

I forgot this wasn't a native feature.

Samsung/OneUI has a good few addons like this. Ability for multiple apps to play sound is good too (same addon) and the ability to output different apps from different sound devices at the same time (built in)

I don't let my phone make any noises, but I do use it for music. Would be nice not to have to turn "do not disturb" on or off to listen to music.

Notifications are tied to ringtone, as far as I can't have silent ringtone but noisy notifications, however media is separate from both these two.

That's how it works now on my pixel.

You don't have to? I use DND all the time too.