This app has 4 sensors- A compass, an electromagnetic field (EMF) sensor, a level sensor and a wifi monitor. The compass displays your heading, current latitude and current longitude. With the electromagnetic field sensor know the strength of the electromagnetic field (EMF) you are exposed to. In case your exposure is more than 100µT, a beeper goes off. With the level sensor you can use your phone as a spirit level. An added feature of a beep when the phone is almost level, helps when working in difficult to reach places. Use the WiFi monitor to check the speed and strength of your WiFi network.