Allow access to the Internet only one program (Android)

Question

Android

There is a smartphone with Android 4.1.2 (it seems that it is not at hand now). It is necessary that, if there is an available wifi network, it can go to the Internet without any restrictions, but if it is connected to a mobile network, only one program can go to the Internet, everything else should not have access to the Internet.
Apparently, you need something like a custom firewall, but I can’t find anything sensible.

Answer 1

DroidWall , for example (needs root).