Do Oximeter Apps Work?

Question: Should smartphone apps be used clinically as oximeters? Answer: No!

This was the question put to Oxford University. 

The study mentions Oximeters as being important, quite explictly:

"The COVID crisis is requiring us to manage patients with as little in-person contact as possible. The assessment of a patient with respiratory problems usually includes measurement of blood oxygen saturation (abbreviated SpO2), using a validated pulse oximeter. This is particularly important in unwell patients with COVID-19, since hypoxia is a serious warning sign for severe pneumonia.1 Whilst in-person assessment would use a standard pulse oximeter on the patient’s finger, few patients have such a technology in their homes. Various technology companies have developed smartphone apps that are marketed as accurate for measuring oxygen saturation."

It goes on to say that one of the claims made by an app company, DigiDoc are "unsound":

The claims made by DigiDoc are scientifically unsound. The app “measures oxygen saturation within 90-100% with an accuracy of 0-4 RSM compared to a medical grade oximeter”. It is not clear what RSM is (is it root root-mean-square error, RMSE?) but if we assume that they are claiming an error of ±4%, then a random number generator with a mean value of 95% and errors randomly distributed between -4% and +4% would give values between 91% and 99%.

Careful analysis of the paper by Tomlinson et al3 confirms the lack of scientific credibility for the DigiDoc app


We do, of course, recommend purchasing our ART-1 finger pulse Oximeter. Accredited under FDA, CE and ISO standards, this qualifies as the necessary home medical equipment to reliably measure your SpO2 levels. 


Greenhalgh T, Koh GCH, Car J. Covid-19: a remote assessment in primary care. Bmj 2020;368:m1182. doi: 10.1136/bmj.m1182 [published Online First: 2020/03/28]