Every time I snap a pic of my buddy the game pumps a tone chord through my phone’s speaker. I have my phone muted and the game set to disable sound effects, and it still makes the noise! (I think it has done this ever since it was added to the game.)
How does it decide of its own accord to override my phone’s setting? Is turning media volume down IN ADDITION TO MUTE required? 
Recognizable
Im not sure under what category of sound it is, but its not the same as the game. I get this aswell sometimes. I can mute it as soon as im in the snapshot screen but i usually forget to do this upfront.
How? I’ve already got my phone set to vibrate mode - no sounds. Everything else on the phone respects that – even the rest of the sounds from the game. I can’t understand how an app has the power to override it.
my android phone has separate volume controls for ringtone, media, system, notifications.
Turning ringtone to 0, sets system and notifications to 0 as well irrespective of where they were, but media is left alone.
In-game there are 3 settings, sounds, music, vibration. Are all 3 unchecked or are some still checked?
And if you drag your finger down from the top of the screen it opens a one-row set of frequently-used options, including wi-fi, speaker, bluetooth, and maybe flashlight or hot-spot. That speaker control is a master 3-way switch, between ON, VIBRATE, and MUTE. It’s meant for the speaker, not the individual sounds sent to the speaker, yes?
It’s meant so people can quickly just set their phone to mute or vibrate when a meeting starts. Or at least it used to be meant for that.
Galaxy S10 btw: Just by clicking the volume down button on the left side of the phone. Seems to work when i do that.