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A new phone app senses vibrations and alerts people to earthquakes. The phone app recognizes sudden shaking of the earth’s surface through sensors in smartphones. The new app is called MyShake. It is the work of four researchers at the University of California, Berkeley. They said they created a worldwide warning system that would inform people and give them time to prepare for earthquakes. Other earthquake apps include QuakeFeed, Quakes and Earthquake. They show where earthquakes have happened, their strength, and any aftershocks. The apps use information from the U.S. Geological Survey. The MyShake app is available only for Android phones. Smart phones are equipped with accelerometers. These instruments measure movement. They also can measure the shaking of a machine, building or other structure. Activity trackers and apps that count steps or exercise activities use accelerometers. Global positioning system, also called GPS, apps also use them. MyShake uses phone accelerometers to measure seismic activity. It has been programmed to know the difference between normal activity and earthquake movements. The smartphone then sends seismic information to the app developers. The software developers say their app is correct 93 percent of the time. Several notifications from one area could mean that an earthquake may be taking place or will take place soon. The app also shows ways to stay safer during an earthquake. The developers say the app will improve as more people use it.