Use NetGuard to stop apps from accessing the Internet on your Phone

NetGuard is a free Android app that stops selected apps (user or system apps) from having internet access on your Android phone. It restricts the apps you specify, from using WiFi, Mobile data or both.

You don’t need a rooted phone to use NetGuard.

The app gives you two icons for each app you have on your phone. A WiFi icon and a Mobile Data icon, tapping on either of them will either allow or restrict access to the app it is on.

Sometimes you want your phone's Internet to be on but your WhatsApp should be offline. Or you want your Facebook to be off so that you won't he receiving notifications but you still want your Internet to be on for other apps.

NetGuard is a smartphone app which allows you to select some apps which shouldn't have access to Internet whiles allowing others to access the Internet. 

You can also decide that some apps should only access the Internet when connected to only WIFI.

I have been using this app for about 2 years. You can also try it.