i called tech support today and was basically told that in order to not have data being used while on wifi i have to turn off my mobile data. this makes no sense to me, if i'm connected to wifi why should i have to then make another change to turn that off (and wouldn't that stop me from getting picture texts, etc)? The times I'm being shown as using data are literally while i'm sleeping, at my house, connected to wifi. i have my wifi set to stay connected overnight, etc. I noticed the same issues going on with my sister's line on my account who has the Iphone5.