I use this oximeter for overnight measurements to see if I have sleep apnea. The readout is continuously saved on my iPhone. I paid around £30/EUR35 for this device and it is worth every penny. For that amount of money, I did not expect hospital-grade accuracy, just a reasonable indication if I should contact my doctor for further research.
For overnight measurements, I wear the oximeter under a mitten so that it doesn't fall off. Even when it's on the finger, my device does not measure continuously unless it is connected to the ViHealth app. I have to open the app before I go to sleep, and then I place the phone with the display facing down since the screen is on all the time.
There are several reasons that I may end up without a complete set of measurements for a night. If I wake up and go to the toilet, I may lose the Bluetooth connection, so I must ensure that the device is still connected to the app before I go back to sleep. If another app is taking over the phone, e.g. to show a notification, I imagine there is a risk that the ViHealth app loses control of the screen and then stops recording, but this hasn't happened to me yet.
The oximeter fits nicely on any of my fingers but after a full night on the same finger it always hurts a bit in the morning, so I usually move it to a different finger if I wake up during the night.
Of course, the result from this simple consumer device are not hospital-grade, but I think even a doctor would say that it does give an indication of how often your blood is less oxygenated. The oximeter's precision is no less than that of the spouse, relative or friend that is claiming that you have respiratory arrests, and if you sleep alone you really don't have much choice before you escalate the problem to your doctor anyway.

Handy and accurate, easy to use. I hope it has a pouch or protector :) fast delivery. It is very easy to read and use and fairly accurate.

I'm always shocked that more people don't have pulse oximeters in their home healthcare kits...The batteries were supplied from the company and were easy to install in the back with a slide cover. This oximeter is very slick looking, I really love the all white design and the display has a white LED display.

Ordinato saturimetro mod FS20F non disponibile in Italia.
Prodotto di qualità, prezzo competitivo, tempi di consegna
dalla Cina veloci (1 settimana data ordine, incredibile)
Lo consiglio.

FS20F Bluetooth Finger Oximeter