The government isn't going to hand to do that, that's already what Google's planning to do anyway. They'd just have to tell Google to take down certain apps so they're no longer on the Google "approved" list, which would deactivate them on your device during next network connection (like most Google "services" on Android, I'm sure these too would bypass the system VPN as well) as well as making them unavailable from the sole allowed download source. You know, like they did with ICE Block already.