elyot, WOW that is amazing it actually uses the sensor on the watch instead of the camera:) I DID NOT KNOW THAT that is why i've never tried them, THANKS:)
Did you need to change settings in the app for it to work using the watch sensor? I downloaded to my X5 and when I tap 'Start' the app says "Could not initialize the camera. Make sure the camera is not used by another application.". Strange that it talks about a camera when it should be able to find my watch's sensor - or at least I should be able to tell it that I have a sensor.
I used Mobizen to see the entire UI since much of it is hidden by the round watch face. There is a menu on top right - the 3 dots icon - but it is grayed out and not usable. I was hoping something like "watch sensor mode" or similar would be there.
I google'd this and couldn't find any answers. I tried disabling the watch's Health app through the applications menu in Android but this didn't do anything (I was thinking maybe Cardiograph was being blocked from finding/using the sensor by the default health app).