Here is another smart wearable device that helps you monitor your health and the efficacy of your CPAP machine. The ViATOM Smart Blood Oxygen Saturation Monitor has a soft silicone ring sensor that is comfortable to wear. It can record your heart rate and motion through the night too.
The device has adjustable vibration alerts to wake you up gently when your blood oxygen saturation level falls below your set threshold. A free software is available to export sleep reports in PDF or CSV format.[where to get it]