I have now had the Scan Watch since November 2020. In that time I have also monitored my sleep pattern with a Phillps Dreamaper and the Health App on my Samsung S10. During this period I have found the data provided by the Scan Watch to be very accurate. I have learnt, after consultations with Medical Sleep Specialists, that everyone sleeps differently. Particularly if one is experiencing undiagnosed sleep apnoea. I am not aware of the technology in the Scan Watch but as the device has been approved by the Therapeutic Goods Administration (TGA) (Australia's regulatory authority for therapeutic goods). I believe the device is very accurate. There are many similar devices in the global market place but I understand that the Scan Watch is the only one with approval for all of its functions.