If you are in Haiti and need to report an emergency situation, send a text message to the shortcode 4636.
This works with any SMS-capable cellphone on the DigiCel network.
Messages sent to that code will be entered into a database. A group of volunteers with an organization called Ushahidi will read each message, figure out where it's coming from, and relay the necessary information to rescue teams. In some cases the response can be extremely fast:
“The average turnaround for us receiving a message and having a geo-coordinated and translated report to teams on the ground is about 10 minutes,” one volunteer told a Wired reporter.
It has already saved lives: In one case, someone sent a message to 4636 about a group of schoolchildren trapped in a collapsed school. Ushahidi volunteers were able to pinpoint the location with great accuracy and send a rescue team, according to the report on Wired.
For more information: The 4636 SMS Shortcode for Reporting in Haiti