My son is getting a Dexcom with Share this week. We hope to get a cellphone to make his numbers visible to us. We do not have wifi available in certain locations, and we would like to maintain access as much as possible. Can anyone give me any approximations on how much data we will need to for the cellphone that will be kept with his receiver? We are trying to make our phone carrier decisions, but the amount of data used will make a big difference in our choice. I understand there are many factors involved, but any information would be greatly appreciated. Thanks!