A consequence of Last game you bought? - #5977 by Phil is that I installed an app on my phone (via Aurora Store), and had some realisations.
- This app needs internet access (which I knew in advance).
- When I installed it there was no talk of internet access.
- When I ask my phone which permissions it uses, the only thing it lists is permission to use the camera (enabled) and access to storage (disabled).
- When I tested the app, it talked to the server without asking me for any access.
All of which led me to learn that unrestricted network usage is not considered to be a special permission by Android. It turns out that there’s a menu option tucked away in the App Permissions UI to actually show you the permissions that an app is using. But you can’t disable anything that wasn’t in the initial list.
I mean… what?!
I can comprehend internet access being allowed by default because so many apps are going to want that, but how is internet access not a permission you can switch off?!
Anyhow, I found https://netguard.me/ which is a firewall written by the author of https://email.faircode.eu/ (which is the email client I have on my phone), so I’ve installed that (via F-Droid), told it to block networking by default, and then whitelisted the small handful of apps I have that should ever require network access (and mostly using the setting which says that they can do it only when the screen is on).