To me, it’s gotta be the microphone
At one time, the bank that i used decided to made an app, and they demand Location, Camera, Contact, Files, Microphone, and SMS, in which they will ask for all of it from the get go and not allowing either one of it will send you in a loop, unable to use the app at all. I bail immediately and continue to use the website.
As for the scariest one, camera. They can see where you are and what your surrounding like if they demand “always allow”.
This stuff makes me grateful that my bank and your bank still maintain a fully-featured website. I would be quite upset if I were stuck with such an app and no website.
After the incident they did made some change to only ask permission for the appropriate function and can allow “while in use”, and gotten rid of location permission altogether, but that incident kinda open my eye on cybersecurity and privacy, because if bank can hire subpar dev for such an important app, then all those gadget with IoT will not have top-notched dev doing their app. I’d rather be a luddite than lose anything important.
Internet
On Android apps connected with a Google account, “Can read, send, and delete emails” scares the shit out of me.
Root
This. Root allows an app to get any permissions and probably even disable all evidence of having them.
It actually allows the app to run as the OS itself.
Drug dealer : Network - Location - Contacts
Facebook : I’ll take all
Facebook? More like FBI. Wouldn’t be the first time.
This depends on what you’re trying to defend against. In my opinion (on GrapheneOS), the “Network” permission, “Modify system settings” permission, “Install unknown apps” permission, and any permission that allows apps to communicate with one another (such as a reduced sandbox, file permission, or app communication scopes). Those are the only permissions that I can think of off the top of my head that could potentially allow an app to phone home.
App communication scopes isn’t the scary thing, it’s the solution. Standard Android sandbox allows apps to communicate if they mutually agree to it. Scopes will allow you to limit that.
Location.
Wifi in apps that have no reasonable need for it, because it’s basically location.
Clearly the only right answer is Internet. Who cares about camera, mic or location when the app cannot send the data anywhere anyways?
Inter-app communication can go around it. And most OSes don’t block localhost connections either.