That's a legitimate question. Did any device on board MH370 attempt communication (or merely check for messages or simply announce its existence) after the airplane went missing?
Answering that question would not be a trivial task, however. You'd need to compile a list of all the cell phones known to be in possession of passengers and crew. And you'd need to screen all those phones against the logs of all cell towers which those phones could conceivably have attempted to contact.
Do you suppose that work been done?
It's just scripts and database searches. No need to be aloft over the South Indian Ocean watching your fuel supply!
Actually it would be a trivial task and should already have been done. They don't need the phones of the passengers/crew -- only the cellphone numbers which they should already have at this point since they have already investigated and cleared them.
They need to answer that simplest of questions -- did any of the other 200 phones onboard also connect with the tower as the plane passed overhead or just the co-pilot's???