Between late Monday and early Tuesday this week, California residents received an Amber alert on their phones about two missing children in San Diego. This was the first time California officials notified the public of a statewide Amber Alert through mobile phones. While this system used to be opt-in, as of this year, people must opt-out if they do not wish receive the alerts.
Last year, the major mobile operators in the US, which cover about 97 percent of the population, began supporting wireless emergency alerts from federal, state, and local government agencies. The messages, formerly called the Commercial Mobile Alert System (CMAS) and Personalized Localized Alerting Network (PLAN), are now referred to as Wireless Emergency Alerts (WEA).
Public officials use WEA to notify the public about alerts issued by the President, alerts involving imminent threats to safety or life and Amber Alerts. The messages are not disseminated through phone numbers and are instead sent through cell towers.
Another mobile-based alert system Ping4alerts! is an app that notifies users of nuclear reactor breakdowns, Amber Alerts for missing children, and disaster relief. The company sells its system to emergency services, who then reach the public by the means of a free app on their smartphones.
