Ann: At-Home Obstructive Sleep Apnoea Study Update, page-201

DROWZLE is a prescription, Class II medical device that consists of stand-alone smartphone-based software (operating on Apple iPhone 7, 8, or X model using iOS v10.0 or later) that records and analyzes respiratory patterns during sleep for the purpose of in-home screening for obstructive sleep apnea (OSA).

https://www.prnewswire.com/news-releases/resonea-obtains-fda-clearance-for-smartphone-based-in-home-screening-for-obstructive-sleep-apnea-300891093.html

I gave a thumbs up for the answer Zodiac, happy that you responded. A quick check on net has the above paragraph. How does that fit?