Where is All My IPhone Data Going?

I'll try to keep this short. I have owned my iPhone 5 for exactly one week today. It's prepaid and it is has 2GB of data for a month. How is it possible that I got a message today warning me I have less than 10mb of data remaining! Seriously I have Wi-Fi at home, work and school so I almost NEVER use the internet or apps when out of Wi-Fi! It really sucks though cause it's going to bill me for the extra when the only time I have used data was to check Facebook a few times on Sat when I went to New Jersey. I checked my settings and it says it has used 84.6mb of cellular data! That's like only 5% of the 2 GB so i don't know what's going on and it took me forever to want to buy a smartphone cause they are too expensive. The guy at AT&T said it was cause I was logged into Facebook and it's using data from that. Apparently not if I've only used 84mb for maybe 1hrs worth of time. He told me to sign out of my account when I'm done but i don't know anyone who does that EVERY TIME. Can anyone please help me!

NEED OPINIONS! Is it safe to buy electronics on eBay from CHINA?

YES/NO

Should I buy an electronic on eBay from China? Is it safe?

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Additional info:

I'm looking for a battery case for my iPhone 5, went shopping today and the ones I found were had warranty, came with customer service, you know the safe kind, but a bit pricey.

I went home and searched on eBay, and I got results for cases like, $10! Dirt cheap! But I'm a bit worried it might explode.

Should I go back to the store for the safe (pricey) one? Or just get one on eBay?

Going from Canada to Darwin Australia, Any Advice?

How long does it take for a work visa to come through? Should I buy an iPhone here or there. Heath Insurance? Money, banking and debit cards. Any other information about Darwin would be great!

Any other information on

Using ICloud to backup iPhone 3G?

I have one of the oldest iPhones 3G (still works) I want to upgrade to an iPhone 5S finally, and I was reading ICloud and it said something about needing an IOS 5 or greater to even use it. Can I backup everything currently in my old iPhone 3G? I don't have much, just want to be able to keep texts, pictures, a few videos, and notes. If ICloud won't work for me, any other options? Any info on this would be greatly appreciated.

Should I get iphone 5 or 5c

I used to have 5 and it's broken. I'm really loving the 5c but I saw allot of drop tests and the screen always shatters. I don't want the 5S because it's expensive and I'm not crazy about it!

How to delete music from my iPhone?

I'm just wondering as I have never had one before and just bought a 3G. I can't find a way to delete music from it. I know that I'm supposed to connect to iTunes. Do I connect from the phone or PC? And then what do I click after connecting? I know I probably sound stupid but I'm really bad with technology.

I followed the instructions on syncing it but when I plug it in for some reason iTunes doesn't recognise it and the devices button does not appear on the side.

How to unlock/jailbreak iPhone 4? - 1

I want to unlock my iPhone but I'm not sure how to get it done without paying 70 to 80 quid for it, I will be willing to get it done for around £20 - £30.

I have the iPhone 4 on IOS 6.1.3 and I can't find a jailbreak for it

Will this case protect my iPhone?

I love how this case looks because it shows off the design of my iPhone and the company says it will protect my phone from dings and scratches. Will it protect my phone if I drop it? It's such a cool case but I need a case that will protect my phone from rough drops.

Here is the case - http://www.amazon.com/...0094CWZ7G/