Background: Pulse oximeter apps became of interest to consumers during the COVID-19 pandemic, particularly when traditional over-the-counter pulse oximeter devices were in short supply. Yet, no study to date has examined or scoped the state of privacy policies and notices for the top-rated and most downloaded pulse oximeter apps during COVID-19.
Objective: The aim of this study was to examine, through a high-level qualitative assessment, the state and nature of privacy policies for the downloaded and top-rated pulse oximeter apps during the COVID-19 pandemic to (1) compare findings against comparable research involving other mobile health (mHealth) apps and (2) begin discussions on opportunities for future research or investigation.
Conclusions: Pulse oximeter app developers should invest in offering stronger privacy protections for their app users, and should provide more accessible and transparent privacy policies. This is a necessary first step to ensure that the data privacy of mHealth consumers is not exploited during public health emergency situations such as the COVID-19 pandemic, where over-the-counter personal health monitoring devices could be in short supply and patients and consumers may, as a result, turn to mHealth apps to fill such supply gaps. Future research considerations and recommendations are also suggested for mHealth technology and privacy researchers who are interested in examining privacy implications associated with the use of pulse oximeter apps during and after the COVID-19 pandemic.
Symptom and health behavior tracking applications or smartphone apps continue to grow in popularity along with government interest and oversight over the privacy practices of such apps . Notably, recent research has raised concerns about the privacy and security of information provided and exchanged via mobile health (mHealth) and wellness apps in general, especially apps that target certain disease or patient populations. For instance, a recent study that examined 29 commercial smartphone apps developed for individuals coping with migraines or headaches (diary and relaxation apps) concluded that the apps shared information with third parties, while also noting that there are few legal protections that protect against the sale or disclosure of app user information to third parties [ ]. Another study deployed a semiautomatic app search module to examine the privacy-related information of diabetes-focused apps available via Android, discovering that nearly 60% of the 497 apps surveyed requested permissions that significantly risk user data privacy and that 28.4% of the apps did not house their privacy policies on a website [ ]. Several other recent studies discovered similar variation in findings for a variety of broadly available mHealth apps, which are discussed further below [ - ].
Pulse oximeter apps became of interest to consumers during the COVID-19 pandemic, particularly when traditional over-the-counter pulse oximeter devices were in short supply, as consumers sought to personally monitor themselves for hallmark symptoms of SARS-CoV-2 infection (eg, low blood oxygen saturation) [, ]. Traditional medical-grade pulse oximeters function using a clamp that can be placed over a person’s fingertip, which then shines a light over the fingertip to measure blood oxygen saturation. Some pulse oximeter apps connect with traditional, medical-grade pulse oximeter devices via Bluetooth or USB and can export data/records to other devices. The US Food and Drug Administration (FDA) defines a pulse oximeter as “a device used to transmit radiation at a known wavelength(s) through blood and to measure the blood oxygen saturation based on the amount of reflected or scattered radiation” [ ]. To obtain a pulse oximetry reading, pulse oximeter devices project a light at a specific wavelength that is shined over a specific area of a person’s body while the device measures how much light is absorbed (vs transmitted) by the blood cells within that area of the body. This process is somewhat similar to how mobile apps collect these same measurements, and studies have examined the differences in performance between pulse oximeter mobile apps and medical/hospital-grade pulse oximeters [ , ].
Consumer Reports recently outlined the pros and cons of using pulse oximeter apps, noting a specific app that is available on smart Android phones, called the Pulse Oximeter-Heart Rate Oxygen Monitor App, developed by digiDoc Technologies. This app is meant to be used only for athletic or fitness purposes and not for medical purposes given its technical performance limitations . However, pulse oximeter apps that rely on flash and camera lighting to measure blood oxygen saturation are not always reviewed and approved by regulatory authorities such as the US FDA. Pulse oximeters recently underwent increased scrutiny during the COVID-19 pandemic due to research highlighting racial bias in pulse oximeter devices developed and trained on nonracially diverse populations of individuals, thereby prompting the need for further investigation regarding the scientific validity and accuracy of pulse oximeters [ ].
Traditional, over-the-counter pulse oximeters became in short supply during the pandemic amid supply chain shortages. Yet, no study has been published to date broadly examining the privacy policies of pulse oximeter apps at the height of the broad societal impact of the COVID-19 pandemic (mainly, during 2020). Specifically, the literature offers no high-level qualitative assessment on the state or nature of privacy policies for the most downloaded and top-rated pulse oximeter apps during this challenging period. Therefore, the aim of this study was to address this gap to compare findings against comparable research involving other mHealth apps, which can begin discussions on how future research can fill important knowledge gaps about the state of privacy practices for pulse oximeter apps during and after the COVID-19 pandemic.
In August 2020, the Google Play Store and Apple Store were searched to scope and identify pulse oximeter apps that had either at least 500 downloads (Google Play Store apps only) or a three out of five-star rating (Apple Store apps only). The total number of pulse oximeter apps available on both the Google Play Store and Apple Store was not tallied for purposes of the analysis. Under the direction of the author, two junior analysts reviewed privacy policies for pulse oximetry–specific apps that met the inclusion criteria between August and October 2020.
This specific information was extracted to align with our prior work to examine the extent to which each pulse oximeter app “appropriately and ethically balanced public health and safety with privacy risks and other interferences with civil liberties” during the COVID-19 pandemic .
These details were captured and summarized independently by the same two junior analysts and the summary was reviewed by RHS for accuracy and clarity. The finalized summary of findings was not reviewed and verified by the developers of the apps that met the inclusion criteria for further accuracy.
Six apps in total met the study-specific inclusion criteria. Three of these six apps connect to or are compatible with an externally associated oximeter device. Among these three, only one provided a statement of FDA approval as a pulse oximeter device (EMAY Bluetooth Pulse Oximeter). The app developer’s headquarter locations were disclosed for all except one of the six apps (OxyCare-[Pulse Oximeter]); apps were developed in Vietnam, Spain, the United States, China, and Canada. Two apps required payment to either download or access certain features within the app (Pulse Oximeter-Beat & Oxygen and Oxxiom).
Privacy Notice Assessment
All six apps reviewed provided some information about the scope of personal data collected upon installing the app. All but one app (OxyCare [Pulse Oximeter]) specifically described how personal data are collected, who can access the personal data, why personal data are used, and where and for how long personal data are stored. Half of the apps reviewed (Pulse Oximeter-Beat & Oxygen, Oximeter, and Kenek Edge) provide an ads disclosure directly on the app download site. Two apps (OxyCare-[Pulse Oximeter] and Oxxiom) did not disclose deidentification commitments within the scope of proportionality, fundamental rights, and data protection and privacy issues. None of the apps’ policies explicitly stated if personal data would be used for research purposes. Only one app’s policy (Oximeter) explicitly stated that personal data are deleted once the app user permanently deletes the account. The five app developers that described who can access personal data in their privacy notices (excluding OxyCare [Pulse Oximeter]) discussed circumstances in which personal data are collected from and used by nonusers (ie, third-party service providers, advertising partners). Two of those five apps explicitly describe personal data access/use by law enforcement (Oximeter and Kenek Edge). Data collection and use for four of the apps are explicitly “opt-in” (Pulse Oximeter-Beat & Oxygen, Oximeter, Oxxiom, and Kenek Edge) and one app explicitly recommends disabling cookies as a privacy safeguard for personal data (EMAY Bluetooth Pulse Oximeter).
|Category||Pulse Oximeter-Beat & Oxygen||Oximeter||OxyCare-(Pulse Oximeter)||Oxxiom||EMAY Bluetooth Pulse Oximeter||Kenek Edge|
|Software purpose||General digital health management app that helps users personally check their blood oxygen level and heart rate at any time||General digital health management app that helps users see the percentage of breathable oxygen at their current altitude and check what percentage of oxygen they are breathing||Digital health app that connects to traditional, medical-grade pulse oximeters via Bluetooth or USB||Digital health app that works only with the Oxxiom pulse oximetry system/device||Digital health app that allows users to transfer the pulse oximetry and heart rate data from the EMAY Bluetooth Pulse Oximeter device (Food and Drug Administration–approved) to smartphones||General digital health management app that helps users measure their blood oxygen and heart rate using a hospital-grade finger sensor that can be attached to users’ mobile phones or tablets|
|Developer location (country)||Vietnam||Spain||Not disclosed||United States||China||Canada|
|Free/Paid||Free to install but charges per feature offered within the app||Free to install and use||Free to install and use||Charge to install; pulse oximeter sold separately||Free to install and use||Free to install and use|
|Mobile device access permissions stated on app download site||Storage; Wi-Fi connection information; wearable sensors/activity data; photos, media, and files; receive data from internet; full network access; prevent device from sleeping; view network connections; run at startup; control vibration||Location; photos, media, and files; storage; view network connections; full network access||Location; photos, media, and files; storage; pair with Bluetooth devices; access Bluetooth settings||Users may post, upload, store, share, send, or display photos, images, video, data, text, comments, and other information and content (“Your Content”) to and via the app, which would grant the app a nonexclusive, transferable, sublicensable, worldwide, royalty-free license to use, copy, modify, publicly display, reproduce, translate, and distribute user content||Not disclosed||Location; weblogs; IP address; web browser information; date and time user accessed or left the developer’s website and which pages the user viewed; behavioral data (eg, sleep patterns); user communication records with the developer; personal information (eg, name, age, gender, height, and weight)|
|Ads disclosure on app download site?||Yes||Yes||No||No||No||Yes|
|Scope of personal data collected||“Registration” data (eg, name, email); “transaction” data (eg, purchases, offer responses, downloads); “help” data; app use (eg, heart rate, steps, flights climbed, age, height, weight); other data (eg, mobile device type, unique device ID, IP address, mobile operating system, mobile internet browsers)||“Account” data (eg, username, password, email); “additional” data (eg, biography, location, website, picture, address book); location data (eg, mobile or IP address); “log data” (eg, IP address, browser type, operating system, referring webpage, pages visited, location, mobile carrier, device information, search terms, cookies)a||Location (approximate via network and precise via GPS); USB storage (photos, media, files)a||Date and times of measurements; SpO2b, PRc, and PId measurements; sale information (eg, shipping address, contact information, credit card information)||Deidentified “basic” web server visitor information (eg, IP address, browser details, timestamps, referring pages)||Visit data (eg, location data, weblogs and other communication data, IP address, web browser information, date and time accessed); form data (eg, name, email); sleep data (eg, actions, behaviors, treatments, medication, and general wellness); identifying information (eg, email, device ID, site password); personal information (eg, name, age, gender, height, weight); location information|
|How personal data are collected||Via individuals (account creation or contacting the app); automatic app collection (eg, device, IP address); and third-party tracking technology (eg, cookies)||Via “various websites, email notifications, apps, buttons, widgets, ads, and commerce services”a||Not disclosed||Self-reported and self-uploaded||Tracking via cookies||Via individuals (account creation, contacting the app/site); automatic collection (eg, device, IP address); and third-party tracking technology (eg, cookies)|
|Why personal data are used||To contact individuals, advertise relevant products and services, to use the app||To provide the app services while improving them over time and to provide relevant advertisinga||Not disclosed||To provide app services||For routine administration and maintenance purposes||To contact individuals, advertise via third parties, perform the app’s services, and comply with the law|
|Where the data are stored||Internal memory of the user’s cellular device. Data processing takes place in the United States||Internal memory of the user’s device(s). Data processing takes place in the United States and any country where the app operatesa||Not disclosed||Internal memory of the user’s iOS device||Not disclosed||Internal memory of the user’s devices; otherwise, not disclosed|
|How long the data are stored||Data for advertising purposes are stored as long as the app is installed on the mobile phone||If the user permanently deletes the account, then the data are deleted. Log data are deleted after a few monthsa||Not disclosed||Credit card information is not stored||Not disclosed||Not disclosed|
|Proportionality, fundamental rights, and data protection and privacy issues||Only aggregated, anonymous data are “periodically” transmitted to third parties. Advertisers will only have access to “Automatically Collected Information,” which is the device’s unique ID, IP address, mobile operating system, type of mobile browsers, and app use information||Nonprivate, aggregated, or “otherwise nonpersonal information” will be shared or discloseda||Not disclosed||Not disclosed||User’s personal information cannot be used to identify specific visitors||Individuals can visit the app/website without revealing any personal information|
|Privacy safeguards||The app is opt-in. Physical, electronic, and procedural safeguards of data (eg, authorization process)||The app is opt-ina||Not disclosed||The app is opt-in||The app recommends disabling cookies||The app is opt-in. The developer has a “commercially suitable physical, electronic, and managerial procedure” to safeguard and secure collected information|
aInformation taken from the app developers’ general privacy policies; the policy could apply to the pulse oximeter app reviewed or a different app made by the developer.
bSpO2: oxygen saturation.
cPR: pulse rate.
dPI: perfusion index.
ePII: personal identifiable information.
The present findings fill an important literature gap regarding the privacy policies of pulse oximeter apps during the COVID-19 pandemic. These findings are largely consistent with trends observed in prior research that has examined the accessibility, structure, and substance of commercial mHealth apps’ privacy policies [- ]. Namely, the top-rated or the most downloaded pulse oximeter apps during the COVID-19 pandemic either did not provide accessible privacy policies via the app store or did not provide privacy policies that were specific to the pulse oximeter app being offered. Thus, the present findings seemingly align with observations seen in recent assessments of privacy policies for a variety of mHealth apps. Although each pulse oximeter app provided some information to users about their scope of data collection, what is perhaps most concerning from a privacy standpoint is that all but one app (OxyCare [Pulse Oximeter]) provided privacy disclosures that are consistent with current privacy recommendations and best practices as well as policy-based guidance.
There are limitations to the present analysis and findings such that the observations reported herein are limited to only the highest rated or most downloaded pulse oximeter apps, which effectively excludes pulse oximeter apps that have lower ratings or are downloaded less frequently. In addition, this analysis did not include technical verification and quality assessment criteria for the apps, such as pulse oximeter app usability. Within these limitations are opportunities for further research to explore these important components as a critical next step to this broad analysis. This study was also cross-sectional in time such that it was intentionally limited to capture the state of pulse oximeter app privacy policies at the height of the COVID-19 pandemic when traditional, over-the-counter pulse oximeters were in short supply. Future research should examine if and the extent to which popular pulse oximeter app privacy policies have been either developed or updated.
Alignment With Prior Research Examining the Privacy Policies of mHealth Apps
|This study||Pulse oximeter apps during COVID-19||6||2 (33)|
|FPF Mobile Apps Study ||Health and fitness, period tracking, sleep aid||25||19 (76)|
|Flors-Sidro et al ||Diabetes||497||139 (28.0)|
|O’Loughlin et al ||Depression||116||57 (49.1)|
|Grindrod et al ||Medication use and management||185||63 (34.1)|
|Rosenfeld et al ||Dementia||72||33 (46)|
|Huckvale et al ||Mental health (depression and smoking cessation)||36||25 (69)|
|Bachiri et al ||Pregnancy monitoring||38||18 (47)|
Future Opportunities and Priorities for Privacy Researchers and App Developers
Based on the present findings, it is recommended that future privacy research on pulse oximeter apps involve a deeper comparative analysis that would investigate the effectiveness of available privacy policies and/or offer a more technical analysis of privacy and security implications. Future work might also involve a systematic review, meta-analysis, or meta-synthesis of mHealth apps to more robustly capture and compare the state and substance of privacy policies and notices for mHealth apps, including pulse oximeter apps. Moreover, given that (1) certain pulse oximeter app user data could be considered as sensitive data under the EU General Data Protection Regulation (GDPR), and (2) each of these apps could function within the European Union and must therefore comply with the EU GDPR, future work should involve a robust risk assessment of pulse oximeter app and other mHealth app privacy policies against specific articles within the EU GDPR, most notably articles focused on user informed consent, data minimization, legal basis or grounds for data collection, data subjects’ rights, and consequential areas . Lastly, pulse oximeter app developers should clarify within their privacy policies their purpose and need to collect sensitive information (eg, geolocation data, browsing data, address book data), as it may be unclear or not intuitive among users why the pulse oximeter app would need to collect such data to provide its intended services or experience to its users, and thus may be perceived as privacy-invasive.
Gratitude is extended to Pollyanna Sanderson, Policy Counsel, and Veronica Alix, former policy intern, at the Future of Privacy Forum in Washington, DC, for their time and effort put forth to conduct the privacy notice and policy analysis reported herein. RHS is the former Health Policy Counsel and Lead at the Future of Privacy Forum in Washington, DC. The views herein do not necessarily reflect those of Future of Privacy Forum supporters or board members.
Conflicts of Interest
RHS is presently employed by the Duke-Margolis Center for Health Policy and reports contract work with the National Alliance Against Disparities in Patient Health.
- Plant M. Does your health app protect your sensitive info? Federal Trade Commission Consumer Information. 2021 Jan 13. URL: https://www.consumer.ftc.gov/blog/2021/01/does-your-health-app-protect-your-sensitive-info [accessed 2021-08-04]
- Minen MT, Stieglitz EJ, Sciortino R, Torous J. Privacy issues in smartphone applications: an analysis of headache/migraine applications. Headache 2018 Jul 04;58(7):1014-1027 [FREE Full text] [CrossRef] [Medline]
- Flors-Sidro JJ, Househ M, Abd-Alrazaq A, Vidal-Alaball J, Fernandez-Luque L, Sanchez-Bocanegra CL. Analysis of diabetes apps to assess privacy-related permissions: systematic search of apps. JMIR Diabetes 2021 Jan 13;6(1):e16146 [FREE Full text] [CrossRef] [Medline]
- Powell AC, Singh P, Torous J. The complexity of mental health app privacy policies: a potential barrier to privacy. JMIR Mhealth Uhealth 2018 Jul 30;6(7):e158 [FREE Full text] [CrossRef] [Medline]
- O'Loughlin K, Neary M, Adkins EC, Schueller SM. Reviewing the data security and privacy policies of mobile apps for depression. Internet Interv 2019 Mar;15:110-115 [FREE Full text] [CrossRef] [Medline]
- Grindrod K, Boersema J, Waked K, Smith V, Yang J, Gebotys C. Locking it down: The privacy and security of mobile medication apps. Can Pharm J (Ott) 2017;150(1):60-66 [FREE Full text] [CrossRef] [Medline]
- Benjumea J, Ropero J, Rivera-Romero O, Dorronzoro-Zubiete E, Carrasco A. Assessment of the fairness of privacy policies of mobile health apps: scale development and evaluation in cancer apps. JMIR Mhealth Uhealth 2020 Jul 28;8(7):e17134 [FREE Full text] [CrossRef] [Medline]
- Rosenfeld L, Torous J, Vahia IV. Data security and privacy in apps for dementia: an analysis of existing privacy policies. Am J Geriatr Psychiatry 2017 Aug;25(8):873-877. [CrossRef] [Medline]
- Zapata B, Niñirola A, Fernández-Alemán J, Toval A. Assessing the privacy policies in mobile personal health records. 2014 Presented at: 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society; 2014; Chicago, Illinois p. 4956-4959. [CrossRef]
- Benjumea J, Ropero J, Rivera-Romero O, Dorronzoro-Zubiete E, Carrasco A. Privacy assessment in mobile health apps: scoping review. JMIR Mhealth Uhealth 2020 Jul 02;8(7):e18868 [FREE Full text] [CrossRef] [Medline]
- Papageorgiou A, Strigkos M, Politou E, Alepis E, Solanas A, Patsakis C. Security and privacy analysis of mobile health applications: the alarming state of practice. IEEE Access 2018;6:9390-9403. [CrossRef]
- Huckvale K, Torous J, Larsen ME. Assessment of the data sharing and privacy practices of smartphone apps for depression and smoking cessation. JAMA Netw Open 2019 Apr 05;2(4):e192542 [FREE Full text] [CrossRef] [Medline]
- Hutton L, Price BA, Kelly R, McCormick C, Bandara AK, Hatzakis T, et al. Assessing the privacy of mHealth apps for self-tracking: heuristic evaluation approach. JMIR Mhealth Uhealth 2018 Oct 22;6(10):e185 [FREE Full text] [CrossRef] [Medline]
- Sunyaev A, Dehling T, Taylor PL, Mandl KD. Availability and quality of mobile health app privacy policies. J Am Med Inform Assoc 2015 Apr;22(e1):e28-e33. [CrossRef] [Medline]
- Bachiri M, Idri A, Fernández-Alemán JL, Toval A. Evaluating the privacy policies of mobile personal health records for pregnancy monitoring. J Med Syst 2018 Jun 29;42(8):144 [FREE Full text] [CrossRef] [Medline]
- Khalid A. Pulse oximeters are selling out because of the pandemic. Quartz. URL: https://qz.com/1832464/pulse-oximeters-for-coronavirus-unnecessary-but-selling-strong/ [accessed 2021-04-28]
- Singh HJL, Couch D, Yap K. Mobile health apps that help with COVID-19 management: scoping review. JMIR Nurs 2020 Aug 6;3(1):e20596 [FREE Full text] [CrossRef] [Medline]
- Pulse Oximeters - Premarket Notification Submissions 510(k)s: Guidance for Industry and Food and Drug Administration Staff. Food and Drug Administration. 2013. URL: https://www.fda.gov/regulatory-information/search-fda-guidance-documents/pulse-oximeters-premarket-notification-submissions-510ks-guidance-industry-and-food-and-drug [accessed 2021-08-04]
- Browne SH, Bernstein M, Pan SC, Gonzalez Garcia J, Easson CA, Huang C, et al. Smartphone biosensor with app meets FDA/ISO standards for clinical pulse oximetry and can be reliably used by a wide range of patients. Chest 2021 Feb;159(2):724-732 [FREE Full text] [CrossRef] [Medline]
- Tarassenko L, Greenhalgh T. Question: Should smartphone apps be used clinically as oximeters? Answer: No. The Centre for Evidence-Based Medicine. 2020 Apr 01. URL: https://www.cebm.net/covid-19/question-should-smartphone-apps-be-used-as-oximeters-answer-no/ [accessed 2021-08-04]
- Peachman R. People Concerned About COVID-19 Are Using Pulse Oximeters to Measure Oxygen Levels. These Are the Pros and Cons. People Concerned About COVID-19 Are Using Pulse Oximeters to Measure Oxygen Levels. URL: https://www.consumerreports.org/medical-symptoms/covid-19-pulse-oximeters-oxygen-levels-faq/ [accessed 2021-04-28]
- Sjoding MW, Dickson RP, Iwashyna TJ, Gay SE, Valley TS. Racial Bias in Pulse Oximetry Measurement. N Engl J Med 2020 Dec 17;383(25):2477-2478 [FREE Full text] [CrossRef] [Medline]
- FPF charts the role of mobile apps in pandemic response. Future of Privacy Forum. 2020 Apr 03. URL: https://fpf.org/blog/fpf-charts-the-role-of-mobile-apps-in-pandemic-response-chart/ [accessed 2021-11-11]
- OxyCare - (pulse oximeter) - apps on Google Play. Google. URL: https://play.google.com/store/apps/details?id=com.berry_med.oxycare&hl=en_US&gl=US [accessed 2021-04-28]
- oxxiom user guide. true wearables. URL: https://www.truewearables.com/img/UserGuide.pdf [accessed 2021-04-28]
- Privacy statement. Kenek Health Support Portal. URL: https://kenekhealth.freshdesk.com/support/solutions/articles/47000272334-privacy-statement [accessed 2021-04-28]
- FPF mobile apps study. Future of Privacy Forum. 2016 Aug. URL: https://fpf.org/wp-content/uploads/2016/08/2016-FPF-Mobile-Apps-Study_final.pdf [accessed 2021-11-11]
- Wolford B. Writing a GDPR-compliant privacy notice (template included). GDPR. URL: https://gdpr.eu/privacy-notice/ [accessed 2021-08-04]
|FDA: Food and Drug Administration|
|GDPR: General Data Protection Regulation|
|mHealth: mobile health|
Edited by L Buis; submitted 11.05.21; peer-reviewed by D Mendelsohn, I Schiering, J Ropero; comments to author 02.07.21; revised version received 05.08.21; accepted 03.12.21; published 27.01.22Copyright
©Rachele Hendricks-Sturrup. Originally published in JMIR mHealth and uHealth (https://mhealth.jmir.org), 27.01.2022.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR mHealth and uHealth, is properly cited. The complete bibliographic information, a link to the original publication on https://mhealth.jmir.org/, as well as this copyright and license information must be included.