I dug deeper. To call the A360 a “watch” is a misnomer. It is specifically a fitness tracking device, with timekeeping capabilities. Watches do not monitor heart rates. Upon investigation, I have learned that the A360 DOES indeed support Bluetooth Smart (also known as Bluetooth Low Energy). It’s important to understand that Bluetooth is a one-to-one communications protocol. In other words, the device may only be “shaking hands” with one other device at a time. If your device is connected to your phone, or another app via BLE, it will NOT be able to communicate with Zwift. You must first UNPAIR your device from any/all other devices before Zwift will be able to “pair” with your A360.
Here’s a helpful article: