I just got a text message from AT&T claiming that I have used more than 90% of my data plan (200MB) and I am only a week into the billing cycle. When I look at my data usage on the AT&T web site, it shows transfers of 15MB, 60MB and 116MB occurring between 10:30PM and 11PM several nights over the last 7 days. The problem is two fold: 1) I am in bed by 9 or 9:30PM every evening as I get up at 5 to 5:30 most mornings. 2) The phone was in my house and connected to WiFi, so it should only have been using WiFi. I have iCloud turned on and had it configured for backups of my iPhone 4. I had the data & documents setting for iCloud configured to dis-allow cellular data use. I have had IOS 5/5.0.1 loaded since it came out. I typically get warnings every other month on having used 65% of my data plan a few days before the billing cycle ends. I have turned off cellular data for the moment and I have turned off the iPhone backup to iCloud and the Data & Documents for iCloud are now off. I believe that I am going to get billed for another 200MBs because the data log on the AT&T web site stops yesterday at midnight. I searched the forum for "excessive data" messages, but all the threads are months old. Does anyone have any other ideas as to what might have caused this beyond something with iCloud and backups? Thanks!