There's nothing worse than not being able to reach family and friends during an emergency. Facebook is updating its Safety Check tool that allows you to check in on your loved ones in times of crisis.
According to Mashable, the feature is like a virtual roll call. It allows users in affected areas--such as places hit by war, violence or natural disasters--to ask friends and family to account for themselves and mark themselves as "safe."
Facebook looks at geo-location data to find which areas are crisis zones. With the update, if Facebook sees users talking about a crisis, the Safety Check prompt shows up and encourages friends to check in. In order to send a Safety Check request, you must be in the affected area.
Here's a screenshot of the feature in action: