AT&T has begun rolling out Wireless Emergency Alerts
updates for iPhone 4S and 5, so you won't be the last folks to know if
the entire northern hemisphere is about to be covered in ice à la Day After Tomorrow. You'll receive a notification from the carrier when your update is ready, but only if you're using iOS 6.1
or higher.
Once installed, AMBER and Emergency alerts are automatically
sent to your phone unless you switch them off via Settings.
However,
should you be tired of Obama, just know that there's no way to switch
off Presidential alerts. WEA messages are always free of charge, so you
don't have to worry about going over your texting limit when notified
that you need to get the hell out of dodge.
Read it on: Engadget