This is interesting, but not yet useful. The iPhone’s accelerometer can detect earthquakes.
It can detect an earthquake stronger than 5.0 on the Richter scale. It can’t really do any good as a way to detect earthquakes early. However, the interesting part is that it is sensitive enough to tell the difference between a legitimate earthquake and someone just shaking the phone when they carry it.
It’s pretty interesting, but we wonder if it can become anything more later.