Why is my iPhone using so much data

My Wife and I have the 200MB plan because we rarely use 3g data. The wife is 90% of time around home Wi-Fi, but for some reason her bill will be 200-400mb above our cap with a hand full of 50-100mb data transfers. I called ATT and they can't tell me exactly what app/ service is doing this xfer, simply that it happened. So long story short, I was wondering if there's a way to audit the iPhone to find out why this 3g data was being used when she physically wasn't punching away at the screen

Sim Card Into iPhone Without Data Plan?

Ok, so my mom gave me her old iPhone to use or whatever, and I'm wondering what would happen if I put my sim card into it and used it? It's the 3G one, and I have an AT&T sim card but I don't use the internet, unless I have Wi-Fi so I would only use my calls and texting (I have unlimited), so would it still charge? I don't want anything to happen. Will I be fine if I just don't use the 3G? Or internet?

How to put a date/time/weather widget on the iphone?

I downloaded this cute widget for weather/time/date for my iphone to be on the top of my homescreen and i put it in the folder as it said on the website and can access it through winterboard, but when i selected it, it doesn't show up on the screen. If i go from my lockscreen onto my homescreen, it will show for a split second as the screen loads then disappears. How do i keep it on there constantly without it disappearing?

is it because i have a theme and wallpaper on there that prevents it from showing up? I even took off the theme and had my original wallpaper on there but it still doesn't show up. I need help! Can anyone help me?

Why isn't my item showing on amazon?

I'm trying to sell my old iPhone, an hour after i put it up it wasn't in the listings
why not?

Added (1). No i didn't check, but i clicked the sell yours here button and added all the details and everything but its gone. I don't want to put it up again yet because i'm worried it might still be on and ill be selling 2

Can a 3rd party Lock my iPhone?

I paid for an unlock for my iPhone online. After a disagreement about the payment, the guy that unlocked my iPhone (by simply contacting an AT&T technician and having them factory unlock the phone) is threatening to lock the phone again. I have the phone and it's working perfectly now with a different SIM Card from a different carrier. Could they really lock the phone back again?

Iphone app that allows me to send and receive texts?

I recently want to switch over to apple and decided to get an iphone. I'm paying $20 a month for messaging alone and I'm going to have to pay another $15 a month for the required data service. I want to only pay for one and was wondering if there's a text messaging app out there that allows me to send AND RECEIVE TEXTS WITHOUT MY FRIENDS HAVING TO GET THE APP? Thanks!

P.S. I use AT&T as a carrier if you need that!

How much data should i get? Verizon share plan?

I'm thinking of getting the verizon share everything plan. There will be three phones (one basic phone for my dad, an iphone for me, and an iphone for my sister) my dad won't use data much but me and my sister will be using it for stuff like email, twitter, instagram, facebook, safari, youtube, etc (just regular entertainment stuff) how much data should i get so we don't go over? And to save data, whenvever we're at home we could just use our Wi-Fi? 4GB, 12GB?

Transferring purchases from iPod to iPhone?

I put a cd into my laptop and downloaded it to my iTunes, but it won't sync onto my iPhone. How do I get it to download onto my iPhone? Also is there any way to transfer songs from my old ipod onto my new iphone even though they're on different accounts? I deleted the email that my old iPod account is on a long time ago and when I got my new iPhone, I made an entirely different account…

Can't drag & drop from iTunes 10.6.3 to iPhone library?

I just tried adding music to my iPhone from iTunes 10.6.3, but it won't let me drag any of the music on my iTunes library to my iPhone library. I've tried dragging them directly from a folder to my iPhone library, but I still had no luck. I'm running on a Mac OS X 10.8.

How to activate my iMessage?

I have an iphone 3GS iOS 5.1.1 and I've always used iMessage before but I started messing with all of my settings and now my iMessage won't turn on. I switch it to "On" and it gets stuck at "Waiting for Activation… "

It doesn't even ask me for my password or anything, it just stops at that.