[userbinator]

but she just does not want to browse a process list to see which process is using the camera.

How do you know until you've tried?

At the risk of provoking a tangential discussion, I don't think keeping users "in the dark" about what's happening is ever a good idea. They don't have to learn if they really don't want to, but deliberate opaqueness is bad --- if anything, it only leads to more learned helplessness and ignorance. Of course, that's probably what companies want in general, since it means they can control users more easily...

[soylentcola]

Additionally, even if the main user of the device will never pull up a task manager or usage log, that info can be useful for a friend, relative, or hired technician who is trying to help them figure out what's going on with their device.

Instead we have to explain to people that their photos aren't "in" the photos app and their music isn't "in" iTunes. It's the thing you mentioned: file managers will just confuse people so let's not include one. Easier to have them think of files as "living" in the apps we assign to open them.