There are obviously cases where a mobile device cannot replace a desktop. For that matter, there are cases where a desktop cannot replace a mainframe computer (

There are obviously cases where a mobile device cannot replace a desktop. For that matter, there are cases where a desktop cannot replace a mainframe computer (bank transaction processing). All technology shifts are about the 90% -- there is always the 10% of jobs that need a mainframe, or a fax machine, or even a telegram.