Question: why do we call them {smartphones} phones?

Today's question comes from davast. The majority (95%) of my iPhone usage is web / email /pim / twitter / xls & doc files / sat nav. All of which have more individual weekly usage than the telephone bit.

Surely they really are PDAs (Personal digital Assistants) or just "Mobiles" now. What do you think? Is it time to drop the 'phone' tag?