I have an iPhone 4s on the Orange/EE network, I have a 500mb allowance but orange have been charging me for an extra £10 every month and claiming it's data, here's the funny thing - I always turn off mobile data and I only use wifi on my phone, could it be location services? I've turned off other things in case it could be that.
Added (1). EDIT: I always close my apps.
См. статью: What's eating up my iPhone data usage?