See if this app works for you (requires root!)

https://play.google.com/store/apps/details?id=com.googlecode.networklog&hl=en

Basically it looks at your data connections and shows where they're going. It should be easy to spot any unusual activity there. A common expected pattern is that most of your searches will point at Google's servers; if you have bandwidth saving on then all of your browsing will also point at Google's servers; and a few outlying apps point at their own things.

Ah I see. I hope it comes out soon but I suspect "near future" means a lot longer. In the meantime you can use this app which works for seeing network traffic of apps but is not as good as this app will be if it's going to be like I think it will.

oddly i just tried to do this this morning after not doing it for years since my nexus 5 era days.

i loaded up https://play.google.com/store/apps/details?id=com.googlecode.networklog like i used to but it appears to only partially work for a few moments i think its the changes since 2015 and 2020 on the android OS.

ive tried tweaking background access permissions and disabling power saving on the app etc and nothing keeps it working beyond a few packets.

is this app sort of what you are looking for but one that works on android 10?

Network log on play store is the best none come close. Netmonitor on fdroid is foss but doesn't provide enough info like packets sent/recieved. Or show a detailed graph of all your connections, domain names.

https://play.google.com/store/apps/details?id=com.googlecode.networklog

Yes, as long as you are rooted. You can download Network Log or install a custom ROM, CM, Resurrection Remix and a few other have that kind of feature, I believe there's also an Xposed module you could use.

For tracking usage https://play.google.com/store/apps/details?id=com.googlecode.networklog

For blocking network access https://play.google.com/store/apps/details?id=eu.faircode.netguard

Network Log

I just did a quick search of 'outgoing connections' and found this

I use Network Log https://play.google.com/store/apps/details?id=com.googlecode.networklog

Network Log.

I actually have this but my question is does it actually limit the stream to just audio or is it streaming video and audio and simply playing just the audio?

In one case you are streaming music but using videos as music would be bandwidth intensive...

Edit: I realized I could just check myself using Network Log.

I used this video and played it once while watching it then played it again with the screen locked

The answer is yes it limits the stream to just audio so you will save bandwidth :D

I realized talking to you I could just use Network Log and check for myself on the streaming and it looks like it does stream only audio.

I used this video and played it once while watching it then played it again with the screen locked

To get it working:

iPhone:

1. Open the video in safari not the youtube app.

2. When the video is playing full screen press the home button.

3. Slide up the music controls from the bottom and press play.

If you need to web browse get chrome because this only works as long as safari is on that page. The only thing I would watch out for is your mobile data, I know when you pay for a youtube music key it streams just the audio but this method may stream video too even if you can't see it.

Android:

you have two more complicated options that I know of. Unrooted users can sideload and/or install a youtube app that can play them like this (you probably wont find them on the play store because youtube removes them.) Your second option, if you have root and Xposed, is to get this module. The Xposed method used to work for me but now it doesn't for some reason... As with above I have no idea if these methods stream just audio or not. If you want to check, get this app and use it to compare the traffic of the youtube app vs these alternates.