What is the main idea of the news item? [originaltext] The power of the mobil

The power of the mobile phone and other social media became clear in the aftermath of the tsunami and earthquake in Japan. Just hours after disaster struck, Japanese volunteers used social media information to create a crisis map. The map indicated hazardous areas and emergency services. Hundreds of people each day posted updates to the map on the Internet, including information from radio stations.
    Crisis maps also helped with relief efforts in Haiti. Thousands of text messages provided information to international aid organizations about shelter, food supplies and sanitation. A mapping team helped pinpoint search and rescue requests for people trapped in the rubble.
    Crisis mapping is also being used to keep track of events in Libya. A map is helping the United Nations to follow a wide range of activities, including relief efforts and attacks by government and rebel forces.