Cellular usage being used while I'm sleeping?

[Declan]

I have a iphone 4s on Vodafone's pay monthly.
My Cellular is being used and it's going up every 5 minutes by KB not MB.
But as you know KB will eventually turn into MB and one day this will have me going over my Data limit (250mb).
I've only tried Double clicking my home button to see if there are any background apps.
Over night i switched push notifications off and left wifi on, when i woke up 500mb of wifi had been used..

WHAT IS USING MY DATA!?

Ps: I have push notifications enabled on Facebook/Instagram/Twitter etc but even when i'm not recieving them, something is taking my mb.

[Peter K.]

The phone needs to update. The stock app always uses your data because it has to update. When you pull down your notifications, you always see new weather reports posted. The iPhone also uses your data.

[Lakeside5]

your data is being pushed to your phone, thus it is charges usuages. Turn off at night.