How to limit my mobile data to Facebook and Whatsapp only?

[Engr Aamir Khan Niazi]

I am using iPhone 5s and loving it.
My service provider is giving me free data for Facebook and whatsapp only so I want to use data for only these apps.

I tried in "Mobile Data" setting but there all apps are not mentioned which are installed on my phone.

When I turned off mobile data for all apps mentioned in Mobile Data setting still my mobile data decreased and I got message from service provider that you are using mobile data for other apps.

 

[Ledsteplin]

They can't tell what's using data. If you have all other apps toggled off for cellular, then it's something else. And not all apps use cellular data. That's why those are not listed. It can be a number of things. Check system services. Thing is, whatever is left using data is probably not using very much. Not enough to be concerned.

 

[SwitchBeach]

Your second screenshot shows that you have cellular data enabled for Facebook Messenger. Your third screenshot shows that you have cellular data turned off for Whatsapp.