Where the general-wellness exemption breaks down: FDA's own decisions on consumer wearables and health apps

Consumer wearables sit on a deliberately fuzzy line. A step counter, a sleep-quality score, or a "relaxation" breathing tool is a general-wellness product that FDA does not actively regulate. Add a claim to detect, estimate, or diagnose a disease and the same wrist-worn sensor becomes a medical device under section 201(h) of the FD&C Act. The dividing line is not the hardware. It is the intended use FDA reads off the labeling, the marketing, and the design of the output.

Two bodies of FDA decisions map that line precisely. On one side are the De Novo grants and 510(k) clearances where manufacturers accepted device status and brought a wearable feature through review. On the other are the warning letters where FDA told a company its "wellness," "lifestyle," or "fitness" product had made disease claims that stripped away the exemption. Read together, they show exactly which claims FDA treats as the trigger.

What FDA has cleared as a device: consumer wearable and digital-health features

The clearances establish the baseline. Once a feature makes a physiological or disease-related determination, FDA has consistently required either a De Novo (for a genuinely new device type) or a 510(k) to a now-established predicate. The features below are all software or sensor functions running on mass-market consumer hardware.

Cardiac rhythm: the most developed category

Heart-rhythm features drove the first wave and now have a dense predicate lineage. The foundational grant was Apple's Irregular Rhythm Notification Feature via De Novo DEN180042, which analyzes Apple Watch photoplethysmography (PPG) pulse data in the background to flag rhythms consistent with atrial fibrillation, explicitly not to diagnose AFib ¹⁵⁴¹⁶⁴¹⁷⁴. That De Novo created the classification that later PPG notification features cleared against, including Fitbit Irregular Rhythm Notifications (K212372) ¹⁵⁵¹⁶⁰¹⁶⁸ and the notification component of Samsung's ECG Monitor Application with Irregular Heart Rhythm Notification (K230292) ¹⁵⁶¹⁵⁷.

A parallel line covers on-demand single-lead ECG recording, which classifies the captured rhythm as AFib or sinus rhythm:

Feature	Company	Number	Function
Irregular Rhythm Notification Feature	Apple	DEN180042	Background PPG analysis, notifies of AFib-suggestive rhythm; not diagnostic ¹⁵⁴¹⁶⁴¹⁷⁴
Fitbit ECG App	Fitbit	K200948	Single-channel (Lead I-like) ECG; determines AFib vs sinus rhythm ¹⁶²¹⁷³
Garmin ECG App	Garmin	K221774	Single-channel ECG on compatible smartwatches; AFib vs sinus rhythm ¹⁵⁹¹⁶³
Samsung ECG Monitor App w/ IHRN	Samsung	K230292	PPG irregular-rhythm notification plus single-lead ECG classification ¹⁵⁶¹⁵⁷
Samsung ECG App v1.3	Samsung	K240909	Background PPG notification plus single-lead ECG recording/classification ¹⁶⁵¹⁶⁶
Fitbit Irregular Rhythm Notifications	Fitbit	K212372	PPG pulse analysis; AFib-suggestive notification, not continuous ¹⁵⁵¹⁶⁰¹⁶⁸

FDA also allowed a step beyond notification into quantification. Apple's Atrial Fibrillation History Feature (K213971, cleared June 3, 2022) is aimed at users 22 and older who already carry an AFib diagnosis, and provides a retrospective estimate of AFib burden, the proportion of time spent in AFib during watch wear, trended over time ²⁰⁵²⁰⁶²¹⁰. The important regulatory signal is the guardrail: the feature is bounded to already-diagnosed users, keeping it out of the diagnostic space.

Sleep apnea: notification is a device, and it needed a De Novo

Sleep scoring is general wellness. Screening for a specific sleep disorder is not. Samsung's Sleep Apnea Feature was granted through De Novo DEN230041 as an over-the-counter software function on a Galaxy Watch and phone that detects signs of moderate-to-severe obstructive sleep apnea in adults 22 and older over a two-night window, explicitly not for users already diagnosed and not a replacement for clinical diagnosis ⁵⁸. Apple's Sleep Apnea Notification Feature (K240929) then cleared as an OTC feature analyzing Apple Watch sensor data for breathing-disturbance patterns suggestive of moderate-to-severe apnea in undiagnosed adults 18 and older ⁶¹³. Both carry the same defensive framing: identify patterns, notify, disclaim diagnosis, and state that absence of a notification does not rule out disease.

Hypertension: the newest wrist-based notification

Apple's Hypertension Notification Feature (K250507) analyzes PPG data opportunistically collected by Apple Watch to flag patterns suggestive of hypertension, for OTC use by adults 22 and older not previously diagnosed ²⁵²⁷. Note the recurring architecture across cardiac, apnea, and hypertension features: opportunistic sensor data, a "suggestive of" pattern output, an undiagnosed-adult population, and an explicit non-diagnostic disclaimer. That combination is the template FDA has repeatedly cleared.

Distinct from the notification features are the many cuffed wrist blood-pressure monitors that actually measure blood pressure. These clear routinely as 510(k)s (for example Omron's K182166 and K182481, which add a "HIGH" indicator above 130/80) ³³³⁷³⁵⁴⁰, and OTC arm monitors with WHO/ISH hypertension indicators such as AViTA's K242193 ³⁰. Measuring blood pressure has never been treated as general wellness.

Over-the-counter hearing aids: a statutory category built on a De Novo

The self-fitting OTC hearing aid category began with Bose Hearing Aid, De Novo DEN180026, cleared for direct-to-consumer sale to adults 18 and older with perceived mild-to-moderate hearing loss, user-adjusted with no professional fitting or hearing test ¹²⁸¹³⁰¹³⁸. That grant seeded a large 510(k) field, including Bose SoundControl (K211008) ¹²⁶, MDHearingAid (K220303) ¹³¹¹³², Jabra Enhance Plus (K213424) ¹³⁹, Eargo 5/6 (K221698) ¹²¹, Nuheara IQbuds 2 PRO (K221064) ¹²⁹, and software-defined entries like Nuance Audio Hearing Aid Software (K243150) ¹²⁰ and the Braun Clear Hearing Aid (K212609) ¹³³. Even a self-fitting hearing aid, marketed without a clinician, is a regulated device.

Consumer glucose biosensors: wellness framing, device clearance

The metabolic-wellness market for people not on insulin is now explicitly a cleared device space. Dexcom's Stelo Glucose Biosensor System (K234070, March 2024) is an OTC integrated CGM for adults 18 and older not on insulin, indicated to help users understand how diet and exercise affect glucose excursions ³¹⁶³¹⁸³¹⁹³²⁷. Signos (K250106) cleared on the same OTC-not-on-insulin logic, adding weight-management framing ³²¹³²³, and a later Stelo (K260935) extended down to age 2 ³¹⁷³²⁰³²⁵. The intended-use language reads like wellness ("understand how lifestyle impacts glucose"), yet FDA still required clearance because the device measures an analyte tied to glycemic status.

Temperature, fertility, and infant monitoring

Wrist and skin temperature plus cycle tracking cross into device territory when tied to a fertility or physiological determination: Ava Fertility Tracker (K200163) measures temperature, pulse, HRV and respiration as an aid to ovulation prediction ²⁷⁷, and Natural Cycles (K231274) cleared to use Apple Watch temperature input as the sensor feeding its fertility algorithm ²⁷⁹. On the infant side, Owlet's Dream Sock was granted De Novo DEN220091 (November 2023) as an OTC pulse-rate and oxygen-saturation monitor ¹⁸⁷, after Owlet's earlier consumer sock had been the subject of FDA enforcement over uncleared pulse-oximetry claims. Standalone wrist SpO2 has been cleared as a conventional pulse oximeter, for example the oCare Wrist Pulse Oximeter (K183556) ⁵⁷⁶⁰.

Where the exemption breaks down: FDA's warning letters

The clearances show the compliant path. The warning letters show the failure modes. Across them, the same fact pattern recurs: a product sold as wellness, beauty, fitness, or lifestyle, carrying claims that FDA reads as diagnosing, estimating, treating, or mitigating disease, and therefore meeting the device definition without the required authorization.

The defining recent case: WHOOP Blood Pressure Insights

The clearest articulation of the boundary is FDA's July 14, 2025 letter to WHOOP, Inc. over its Blood Pressure Insights (BPI) feature ¹⁰⁷. FDA cited WHOOP's claims that BPI provides "daily systolic and diastolic blood pressure estimations," offers "a new way to understand how blood pressure affects" performance and well-being, and delivers "medical-grade health & performance insights" ¹⁰⁷. FDA concluded BPI is a device because estimating blood pressure is inherently associated with the diagnosis of hypertension or hypotension, and pointed to the design of the output, a color-coded gauge producing a blood-pressure reading, as evidence of intended use ¹⁰⁷.

Critically for anyone relying on the general-wellness carve-out, FDA expressly rejected WHOOP's general-wellness argument on two independent grounds ¹⁰⁷. First, BPI is not a healthy-lifestyle function because it implies a causal link between blood-pressure measurements and wellness and is not unrelated to disease. Second, even if evaluated under the general-wellness policy, BPI would not qualify because it is not low risk ¹⁰⁷. That two-part test, disease relationship and risk level, is the operative filter, and BPI failed both.

The contrast with Apple's Hypertension Notification Feature (K250507) is instructive. Both address blood pressure on a wrist. Apple submitted a 510(k), bounded the claim to a "suggestive of" notification in undiagnosed adults, and disclaimed diagnosis ²⁵²⁷. WHOOP marketed a numeric "estimation" as a wellness insight and did not obtain clearance. Same physiology, opposite regulatory outcomes.

Diagnostic and screening apps marketed as consumer tools

FDA has repeatedly pulled software back across the line when it claims to screen or pre-diagnose:

Opternative, Inc. (October 30, 2017) for its online eye-examination mobile app, marketed without clearance and intended to diagnose eye conditions ¹¹³¹¹⁶.
SeniorLife Technologies (August 21, 2025) for the SeniorLife.AI app, citing claims of "AI Agents for mobility and cognitive health," that it "proactively identifies fall risk," and offers "a 5-minute gaze-based test on an iPad to detect early signs of Alzheimer's" as a "quick pre-diagnosis." FDA deemed it an adulterated device with no PMA or IDE ¹⁵².
Uscom Kft (July 30, 2025) for the SpiroSonic AIR spirometer paired with a Bluetooth phone app, found adulterated and misbranded for lacking clearance, with the phone app treated as part of the device's intended use ¹⁵³.
Carematrix, Inc. (July 3, 2008) for the Carematix Wellness System, whose name signaled wellness but whose claims to diagnose asthma and COPD and monitor PEFR/FEV made it a device ¹¹⁴.

"Bioresonance," "energy," and scanner claims on consumer hardware

The most aggressive claims attach to consumer-styled devices asserting whole-body scanning or energy healing:

RoyalVibe Health Ltd. (November 18, 2022) over a product line including the CellQuicken Analyzer, a smartwatch-and-software product claimed to "scan your entire body in less than 60 seconds" and "help detect the root cause of your condition," alongside app "treatment" protocols for Alzheimer's, stroke, cancer, and arthritis ¹⁰⁵¹¹⁰⁹⁴. FDA read the scan claims as diagnosis and the protocols as treatment.
ZYTO Technologies (June 21, 2023) over the ZYTO Hand Cradle GSR and software that identified "stressors" as diseases such as Alzheimer's, HIV, Parkinson's, and melanoma and recommended "balancers" as treatments ¹¹¹.
Tesla BioHealing, Inc. (August 10, 2023) over "MedBed" and "BioHealer" products claimed to normalize glucose and blood-pressure levels and treat cancers, stroke paralysis, Lyme disease, and Alzheimer's via "Life Force Energy" ¹⁰⁸.

Light therapy and neurostimulation sold as beauty or wellness

Aesthetic and "brain wellness" devices lose the exemption on treatment claims:

Marci Beauty LLC (February 2, 2021) over LED light-therapy units claiming to "treat sun damage and prevent skin cancer growth," treat rosacea and eczema, and (for one product) treat osteoporosis, asthma, diabetes, and mood and sleep disorders ⁹¹.
Ostar Beauty Sci-Tech (December 4, 2023) over LED masks and a laser hair-growth cap with anti-aging, anti-inflammatory, acne, and follicle-stimulation claims ⁹³.
NeuroField, Inc. (February 28, 2022) over pEMF/neurostimulation systems marketed as "physical therapy for the brain" and to treat arthritis, fibromyalgia, and PTSD, beyond the cleared biofeedback classification ³²⁹.
Axiobionics (December 6, 2012) over "Wearable Therapy" electrical-stimulation garments claimed to manage and treat upper-extremity muscle paralysis and reduce pain ⁹²⁹⁹.
The Avalon Effect (November 5, 2012) over the "Quantum Series Personal Wellness Pack," where testimonial claims of resolving pain, migraine, and joint problems established a device intended use ⁹⁶.

The operating rule FDA's decisions reveal

Put the two datasets side by side and the boundary is consistent. A feature stays in the general-wellness zone only when it avoids a disease determination and stays low risk. It becomes a device, requiring De Novo or 510(k) authorization, once it does any of the following:

Estimates or measures a clinical parameter tied to a diagnosis. Blood pressure estimation (WHOOP BPI) ¹⁰⁷ and glucose measurement (Stelo, Signos) ³¹⁶³²¹ are devices regardless of "wellness" packaging.
Screens or notifies for a specific disease. AFib notification (DEN180042), sleep apnea detection (DEN230041, K240929), and hypertension notification (K250507) all required clearance even when disclaimed as non-diagnostic ¹⁵⁴⁵⁶²⁵.
Claims to treat, mitigate, or cure. Light therapy, neurostimulation, and "energy" products fell on treatment claims ⁹¹³²⁹¹⁰⁸.
Claims to diagnose or "pre-diagnose." Eye-exam, cognitive-screening, and body-scanner apps fell on diagnostic claims ¹¹⁶¹⁵²¹⁰⁵.

The WHOOP letter is the cleanest statement of the underlying test: to keep the exemption, a software function must be unrelated to disease and low risk, and failing either prong is enough to lose it ¹⁰⁷. The successful clearances show the compliant mirror image of that test, a "suggestive of" output, a bounded population (often undiagnosed adults, or the inverse for burden features), an explicit non-diagnostic disclaimer, and a submission on file. Companies that keep the wellness framing but add the disease claim, without the submission, are precisely the population FDA's warning letters target.

FDA-Cleared Wearable Features and the Limits of the General-Wellness Exemption