Review on LIVLOV V9 Bluetooth ANT+ Heart Rate Monitor Armband - Rechargeable HRM Sensor with IP67 Waterproof Rating - Optical Armband Heart Rate Monitor for Peloton, Zwift, Wahoo Fitness, Polar Beat, and Endomondo by William Bradford

I have been using LIVLOV V9 almost every day for more than 3 months. So far I am very happy with my purchase. I only used Bluetooth (didn't try Ant+). The Bluetooth connection worked immediately and there were no problems. Apps used: Polar Beat and Wahoo work fine (Bluetooth connection within the app). Accuracy: Seems good based on my heart rate test. No connectivity or performance issues. I had an issue with the first device that held a charge: sometimes it didn't hold a charge well for several days instead of a few weeks). There was another problem that I didn't notice: the drawing and the information given by the indicators. I contacted support to describe the charging problem and they replied (within a few hours) that the problem was with the chip. They sent a replacement which arrived within a few days. The replacement worked well in every way: I now have all the lights the right color, as well as accurate heart rate and stable Bluetooth.