This is the heart rate monitor that wirelessly transmits pulse readings to an iPhone. The monitor straps comfortably to a forearm and automatically transmits readings via Bluetooth to an iPhone. A free app displays real-time pulse readings, target heart rate zones, calories burned, distance traveled, and speed. The app allows you to input your weight, age, and gender to ensure accurate readings and provides audible prompts to help you maintain the ideal target heart rate. You can select a workout based on time, speed, or calories burned, it provides full access to the iPhone music library, and workout progress can be monitored through graphical workout summaries. Monitor operates for up to five hours after a two-hour charge via the included USB cable. Compatible with iPhone 3GS, 4, and 4S and iPod Touch (3rd and 4th generations). Monitor face: 1 1/2" W x 1 1/2" L with an adjustable strap. (1 oz.)