Add one more item to the list of things you need to make sure you have prepared before you board a plane headed back to the United States:  charging your cell phone.  In an effort to add another layer of security, the TSA is implementing a crack-down on uncharged electronic devices on airplanes that are bound for the U.S.

The threat that TSA officials are trying to lower is the use of so-called "cell phone explosives".  Under new guidelines, passengers who carry electronics on an airplane that is bound for the United States must power them up before being able to board the plane to demonstrate that they have not been hacked.  At this time it's unclear what the restrictions are for brand-new, unopened phones that are still in their packaging.

Read more here.