Ok so I'm getting my new ipad 4 tomorrow. I'm selling my ipad 2 on Craigslist and people keep asking is the 3G is with AT&T or Verizon. I know it's AT&T because that's my carrier but I'd there another way to tell? It should say so on the box or the ipad shouldn't it? Honestly I thought as long as you had 3G it would work on whatever carrier the person had.