Meet the EPSON PS-500: an activity tracker that provides 24/7 heart rate monitoring. It can store up to 20 days of data. The device is useful for heart rate zone training. It has a compact design and can be worn day and night. The mobile app, web portal, and LCD let you review your data easily. You can easily review your data to see how far you have come. The app provides you with personalized information to help you reach your goal. You can get yours for $199.99.