Originally Posted by netguarduser
I don´t think that the connection is made this way, because when I "only use Wifi" then the source connection is from my Wifi local IP, or internal IP 192.168.1..., and when I use "4g only" then the source connection is an IANA address: 10.144.178.114
So, the source address isn´t always from 4g, nor from my real IP, only from my local IP.
What I was trying to get at, is how to isolate your device from any possible internet access under the booting up, before Netguard has had a chance to start up.
This is not trivial to do, depending on what wifis there may be near you, but especially wrt to which mobile operators may be available.
You can of course turn off WiFi in your device and put it in airplane mode, before rebooting it.
If things work as advertised, that should work and allow Netguard time to start up before you activate either the WiFi or the gsm network.
But there is no way to easily verify that neither WiFi nor the cell radio modem are activated surreptitiously by something in your device, i.e. without special monitoring equipment of some kind.
It does boil down to whether you trust the OEM manufacturer, the ROM you are running, and even Qualcomm I suppose.