Ok, so I was using my iPhone as I usually do and I decided to check how much data I had used, I find out that both in the sent and received slots there has been an increase of 4GB, 8GB in total. This freaks me out because I browsed for 10 minutes tops, posted some messages on Facebook and checked my email (there were no attachments). I know that this increase happened suddenly because I checked how much data I had used on my say to school in the morning. When I was getting back home I checked and it went from 1.8GB to 5.8GB for sent data and from 17.6GB to 21.6GB for recieved data. My concern comes because my unlimited data plan (in Mexico) has restrictions, if I use more than 3GB in one month they slow my network connection to 64kbps. I don't know if this is a real value because it has never happened before.