Nowadays, we use our phones for almost everything. What is the ONE thing we will never be able to do with mobiles?

not contact physically to any thing

optimized privacy ,user trust 

letting them out of our lives

we can't get off mobiles and we can't physically contact

We can not get life from a mobile

its never be able to do

designing windows apps

are you serious about this question? 

Making it to do physical work,

Social interactions with emotional gestures and hearty voices. Definitely.

To get in touch physically with the persons in contact.