Did passengers on Malaysia Airlines Flight 370 try to send messages the night the plane vanished?
If they did, those final goodbyes to family members and friends could also be crucial to the investigation.
If and when the plane is found, forensic experts say personal cell phones will be key to solving one of the biggest aviation mysteries in history.
But can data be retrieved from cell phones that have been at the bottom of an ocean for more than six weeks?
CNN's Ted Rowlands is OutFront with the story.