The news is full of stories about interest in and growth of cloud computing ... relying on services hosted on servers owned, operated and maintained by others. Some get nervous about having their information located in places they don't control. The growth of smartphones should, however, accelerate the move to cloud computing and gradually ameliorate those fears.
Relying on cloud computing with a smartphone, or tablet, isn't an option. It's all controlled "in the clouds." Faster and more reliable networks will also help. Over time, whether computing is done on your device or in the cloud should become a somewhat meaningless distinction.