Android Apps As Adversaries

I want to be able to run an app that insists on all sorts of permissions that I'd rather not give it. There are many that could be given more restricted access to sensitive data or fake data rather simply.

Back in the day, CyanogenMod did some of this stuff, but it went under before getting to the point I thought they were heading for :-(

Local file storage should be (by default) restricted to one directory used only by that one app and the file manager

Requests for location data could easily always return some fixed value, ideally with the indicated accuracy set to a low value

Apps that insist on being a device administrator could be told they are without their changes to system settings changing anything other than what they're told the system settings are

Information about wi-fi/mobile networks etc. could be configured to always give the correct lie configured for each app

Demands to be always active or start on boot-up can be ignored

All sorts of fingerprinting relevant stuff like wallpapers, installed apps, localisation, etc. could be faked to an extremely bland default (just the Google default Google config)

While we're at it, an advert blocking proxy would be nice, though probably somewhat more subtle to implement, many apps will simply fail to work if they don't get their adverts to serve and faking them might be both fiddly and app specific...