The BioLogic Bluetooth Smart Heart Rate Monitor belt transmits your heart rate to your phone and compatible application in real time, allowing you to track your workouts and efforts without any other special device. The heart rate monitor works with all devices with Bluetooth Smart, including iPhone 4s and later versions of the iPhone, but also any other Android smartphone with this technology. The energy-saving coded transmitter offers approximately 200 hours of battery life. The electrodes are integrated directly into the textile belt. The BioLogic Bluetooth Smart cardio belt associated with any cycling or running application is the ideal accessory for any athlete, on a bike or on foot, wishing to monitor their cardiovascular frequency.