iOS-CoreMotion-Example - Core Motion in iOS using Swift
Users generate motion events when they move, shake, or tilt the device. These motion events are detected by the device hardware, specifically, the accelerometer and the gyroscope. The Core Motion framework lets your application receive motion data from the device hardware and process that data. Now create an instance of CMMotionManager object. The app can use it to receive four types of motion: raw accelerometer data, raw gyroscope data, raw magnetometer data, and processed device-motion data (which includes accelerometer, rotation-rate, and attitude measurements).