Comment by pests

You seem flabbergasted so I wanted to directly answer your questions.

> how could it access the wireless-networks-based and satellite-based location data?

The OS is either running on the same hardware as Android or has the same direct hardware connections.

> I thought that access to these things is controlled by Android.

Only for things executing within Android. This is just a fancy UI - Android doesn't actually control the hardware.

> In other words, when I turn off e.g. satellite location data in Android, can IZat (which, according to your post, runs outside of Android) or other similar spyware keep secretly using it anyway?

Yes.

> I suppose that the location data can be collected by sniffing the low-level communication between the radio device and Android kernel, provided that it has been enabled in Android first.

You shouldn't think of it as between the radio device and Android but rather between the radio device and the CPU. A CPU that another OS can and is running on. Android is not special here.

> But even then, how could this location data be transferred out of the device?

The same way Android sends data out of the device. The OS asks the CPU asks the radio to transmit some data. Bog standard.

> Are these "parallel-running" OSs also able to somehow "tap into" Android's network layer and send the collected data out?

Yeah but like I said its not Android's network layer. Android is a guest on top of the system just like any other OS running.