Hacker News Reader

For this case you are out of luck since the network provider tracks you through their cell towers.

For spoofing data for apps, if you are on android and have a rooted device there is xposed with xprivacy

This may have changed with android P but AFAIK you don't need root to spoof location data.

I personally have used this app to fool certain retail apps to check in-store prices of items.

i think these solutions use the debug api, not sure.

xprivacy allows for spoofing all kinds of data like phonebook, calendar, even allows to not expose the clipboard.

if only gps data is relevant, this non rooted solution is of course easier to set up.

Root won't help, the modem has its own OS.

Of course it won't. even if you could it would not matter because the cell towers know where you are.

My mentioning of xprivacy was only to further knowledge that you can at least spoof data for the software side (apps installed on the device)