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.
It's man versus bird in Maryland - and the birds aren't backing down.
CNN's Jeanne Moos has the story.
The death toll from the capsized ferry rising tonight to 181 people - and 121 are still missing.
So why did the ship suddenly take on water?
Investigators are now taking a closer look at renovations made to the ship last year.
A South Korean politician claims the ship's owner expanded the top floor of the ferry, making room for an additional 117 passengers.
The extra weight may have shifted the center of gravity.
First distress call on S. Korean ferry from passenger, not crew, coast guard says
Officials are also looking at whether cargo was properly story in the hold.
Kyung Lah reports on the growing frustration as the search and rescue continues.
Malaysia's Prime Minister tells CNN that he will not declare Flight 370 is lost.
As officials search for answers, investigators are still focusing on the pilot and the crew.
Sumnima Udas spoke with the wife of one of the flight attendants and she has this OutFront exclusive.
Jindo, South Korea (CNN) – A South Korean lawmaker said Thursday that renovations last year expanded the top floor of the Sewol, the ferry that sank last week, to make room for 117 more passengers.
Investigators want to know if the modifications made the ferry more likely to capsize.
Kim Yong-rok, an opposition lawmaker who represents Jindo, an island near where the ship sank, told CNN that the modifications raised the ferry's center of gravity.
Kim said the work on the ferry took place in 2013, after the Sewol was purchased from a Japanese company. The ferry's passenger capacity was expanded from 804 passengers to 921 passengers, he said.