Yes, they all have flow sensors. They track vast quantities of data, in fact they track and record the flow of every breath on SD card and can upload that data

Yes, they all have flow sensors. They track vast quantities of data, in fact they track and record the flow of every breath on SD card and can upload that data via Bluetooth. There's an open source app called SleepyHead that can show you all the data in detail. It appears the maintainer burned out but the downloads are still available. So it seems modern CPAP has all that's needed? Doctors can even monitor it remotely or via the cloud. It's intended to let clinics monitor patient progress without needing visits, so it's all pretty easy to use.