Let me see if I understand correctly, you can access the Internet and email when on wifi, however when not on wifi, none of this works? Is this correct? If so, do you have a data plan with your carrier? Do you have cellular data turned on in Settings? When you look at your carrier in the upper left corner, do you see a signal, carrier name, and then 3G, 4G or LTE displayed? Have you contacted your carrier about this?