My data usage on my iphone 4 is almost at its limit. I notice that the usage would randomly go up even when I'm not using the phone!
I really don't want to pay the extra $ but I don't know how to make it stop.
I've disabled all the wi-fi & other related things on the settings and I've even went on plane-mode. I can't even call or text now and it is really bothering me. Plus, this is not the main phone so I can't end the plan either. I would really like to know how to disable the Internet.
Maybe you have lots of apps running in the background. If you double tap the home key you can see a running list of everything so that could be why it goes up quickly. Maybe that could be what it is. Anything that constantly updates and everything is what causes your phone to increase data usage. It takes some times hrs to update the number so it might seem like all at once. Do you Facebook or anything or get lots of notifications?