I am so glad I am not the only one with this problem.  I too bought an Iphone for my son, age 14 and the data usage has gone through the roof. I called AT&T an hour ago and guess what?  Smart limits won't help me at all with the Iphone...I took it away from him last night for not doing homework and now I can't reach him since I have the phone....I don't understand why these phones can't be monitored, so now I will give it back to him and add time of day restrictions for homework time, chores, etc.  I agree with the earlier post that I will probably spend most of my time activating/deactivating the time restrictions on the phone because of this deficiency in the smart limits system...he watched videos, streamed music and watched a movie and that sent me over the 2Gig in less than two weeks....I have zero control with the iphone....