I am looking for a way to limit read access for certain folders, for privacy reasons.
E.g. I want to have a folder that will be used for sensitive data. It shall only be accessed by a file manager app, office app, and picture gallery. And nobody else shall be allowed to read it (e.g. untrusted apps that may violate my privacy).
I am rooted, with CM11. Is there any existing solution for that? Or will it be a dirty hack?
I am thinking of creating a new user group, assigning the "private" folder to this group, and adding the apps (additionally) to this group. Is this possible? Or will I mess something up when doing this? I have a rough overview how the linux user system works, but I do not really know how the android users work in detail.