I’ve seen your likes on my other Airrunner posts, so you will know that I use Stryd for speed and cadence. However, I just tried pairing my Airrunner with Zwift on my tablet and I got it to work twice, with one failure in between successful attempts.
It appears the Bluetooth pairing is not remembered and must be re-made each time you want to connect. Furthermore, if the connection drops then it might not be restored successfully.
For example, the first pairing was successful and led to the example above. I then went to the Zwift pairing screen, which seemed to start things over, and although I could see and select the Airrunner, the was no speed transmitted. I had to press the Bluetooth activation on the Airrunner once again to re-pair the treadmill and Zwift. This time the speed was picked up again, as with the very first connection attempt.
There is none of this nonsense with Stryd (which you will note is connected as my cadence sensor, even though I was not wearing the Stryd and did not (knowingly) activate it). It’s just always discoverable via Bluetooth, even when “dormant”.
At least the speed shown in Zwift did match the speed displayed on the treadmill, allowing for rounding and lag. Personally I would not bother with it again, not least because I have Stryd, which is 100% reliable so I have no interest in hoop jumping every time I hit the treadmill. But maybe it will work well enough once you get to grips with its short attention span.