The Viiiiva heart rate monitor provides heart rate and R-R interval measurements simultaneously through both ANT+ and Bluetooth. Viiiiva works with ANT+ watches and bike computers and with Bluetooth enabled phones. Viiiiva's bridging functionality can collect data from ANT+ sensors (power meters, speed/cadence sensors, footpods) seamlessly, in real-time, and transmit this information to any Bluetooth enabled device. Viiiiva can also store sensor data internally so you can leave your phone, watch or head unit at home and upload your activity later.