Sleep tracking by voice

I am a little concerned about having a mobile phone every night near my head for 8+ hours so I’d like to request or ask whether you thought of the possibility to track the sleep phases by voice (I once had an app that did just that pretty reliably I think).
Otherwise I’d like to thank you for the great app!

Hello Michael, what about the sonar feature, use implemented a little radar or more precisely sonar to the app… and it has detect even breath rate from your abdominal movement, on most phones the effective distance is up to 1 meter… Please see here: https://www.youtube.com/watch?v=cjXExBj6VcY

Detection from hearable sounds would not work especially if there are two people in the bed…