Comparison

Function Health vs BIDSleep

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Function Health

Take control of your health with comprehensive lab testing, personalized protocols, and AI-powered insights. Understand your body's data, track changes over time, and make informed decisions for long-term wellness. Connect wearables and upload records for a complete health picture.

Highlights
  • 160+ lab tests annually
  • Personalized health protocols
  • Private AI Chat for results
  • Connect health wearables
  • Advanced MRI & CT scans
  • Upload health records
Features
Read full description

Function membership helps you take control of your health with 160+ lab tests each year, personalized Protocols, and Private AI Chat—all backed by advanced science and your real data. Built with top doctors, Function gives you the power to understand your body, track how it evolves, and make meaningful change. NOW AVAILABLE: HOME OR OFFICE BLOOD DRAWS Schedule a concierge blood draw at your home or office. A licensed specialist comes to you and completes your blood draw in under 20 minutes. Available in select locations. 160+ LAB TESTS Membership includes testing for your heart, hormones, thyroid, liver, kidneys, toxins, nutrients, inflammation, autoimmunity, immunity and more. ADVANCED MRI & CT SCANS Detect early signs of cancer and hundreds of other potential conditions with the option to purchase advanced imaging for your brain, pancreas, liver, spine, ovaries, prostate, heart and much more. PRIVATE AI CHAT Ask questions about your results, identify meaningful patterns, and figure out where to focus next, with Private AI Chat—built in partnership with top clinicians. CONNECT WEARABLES Connect Apple Health and other health devices and wearables to see how your activity, sleep, and daily habits affect your lab test results and long-term health. PROTOCOLS Translate your lab results, scans and health history into clear, evidence-based plans for nutrition, activity, and supplements—all customizable to your goals and preferences. UPLOAD HEALTH RECORDS Upload past lab test results, scans, and other medical records for a more complete view of your health, all in one secure place. PROGRESS YOU CAN SEE Twice-yearly and On-Demand testing helps you track your results over time, monitor for early signs of disease, and identify where to focus next. ADVANCED LAB TESTS Membership includes 160+ lab tests, plus the option to purchase advanced On-Demand tests for: - Detection of 50+ cancers - Alzheimer’s risk detection - MTHFR gene variants - Advanced MRI and CT scans starting at $365 - Food allergies and sensitivities - …and much more ACCESSIBILITY What could cost as much as $15,000 on your own is included with membership for just $365/year. Lab testing is available at over 2,000 lab locations across the US, with no insurance needed. SECURITY Function was built for privacy and security. Function is built to HIPAA standards. Your information is secure. How it works: 1. Join Function and schedule your first set of lab tests. 2. Get your results and personalized Protocols. Ask questions with your Private AI Chat. 3. See your progress with 60+ lab tests at your Mid-Year Test. 4. Purchase MRI or CT scans and other advanced On-Demand Tests any time. DISCLAIMER Function Health is a technology company and not a laboratory or medical provider. All laboratory and medical services are provided by independent third parties. Function Health does not offer medical advice, laboratory services, a diagnosis, medical treatment, or any form of a medical opinion; its services are not a substitute for medical care, medical advice, and/or a detailed discussion with a physician or other licensed provider. If you have any questions regarding any laboratory results or any other information that you access through Function Health, you should contact a physician or other licensed provider. All material, information, data, and content that Function Health provides is strictly for general information purposes. For additional important information: https:// www.functionhealth.com/terms-of-service.

About

BIDSleep

This app records heart rate, blood oxygen, and motion data from your Apple Watch for personal wellness tracking. It does not offer analysis or diagnostics, focusing solely on data collection and export.

Highlights
  • Heart rate recording
  • Blood oxygen (SpO₂) logging
  • Motion data collection
  • Optional sleep stage tracking
  • Data export
  • Personal self-monitoring
Read full description

App Purpose BIDSleep is a wellness app that helps users collect heart rate, blood oxygen (SpO₂), motion, and optional sleep stage data during rest or overnight sessions. It is designed solely for personal data logging and self-monitoring purposes. Use of HKWorkoutSession To enable higher-frequency physiological data collection (e.g., heart rate approximately every 5 seconds), BIDSleep uses HKWorkoutSession with the .mindAndBody activity type. This is required because alternative background methods like WKExtendedRuntimeSession do not allow sufficient sampling rates. No Analysis or Interpretation BIDSleep does not perform any health analysis, sleep scoring, or diagnostic interpretation. It simply facilitates the collection and optional export of raw physiological data from the Apple Watch and HealthKit for the user’s personal reference. Privacy All collected data remains securely stored on the user’s device and is never transmitted, analyzed, or shared without the user’s explicit consent. Disclaimer BIDSleep is not a medical device and does not provide any health diagnostics, treatment recommendations, or clinical functionality. It is intended only for general wellness and self-tracking use.

Screenshots

Function Health4 screens
BIDSleep4 screens

Verdict

The call

The clearest difference is rating: Function Health at 4.9 against BIDSleep's 2.0. Function Health also leads on review sentiment (62% vs 25%) and ratings volume (25K vs 4). BIDSleep's advantage is monetization model (free vs subscription). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Function Health holds the better App Store score, 4.9 against 2.0. That said, the two scores are not equally well evidenced: Function Health has 25K ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 62% of Function Health's written reviews are positive against 25% of BIDSleep's.

Scorecard4 real differences · 6 level
Function Health versus BIDSleep: the parameters behind the verdict, then further details
ParameterFunction HealthBIDSleep
PriceFreeFree
Rating4.9 (25K ratings) — better2.0 (4 ratings)
Positive reviews61.9% of reviews — better25.0% of reviews
Number of ratings25K — better4
Update frequencyWeekly
AdsNoNo
In-app purchasesNoNo
MonetizationSubscriptionFree — better
DevicesiPhoneiPhone, Apple Watch — better
Requires iOS16.416.0 — better
Further details — not scored
Size199 MB3 MB
Age rating17+4+
DeveloperFunction HealthJoyita Dutta

Customer experience

Function Health

All ratings24,661 ratings
Positive99.0%
Neutral0.4%
Negative0.6%
Written reviews341 reviews
Positive61.9%
Neutral5.6%
Negative32.6%

BIDSleep

All ratings4 ratings
Positive25.0%
Neutral0.0%
Negative75.0%
Written reviews4 reviews
Positive25.0%
Neutral0.0%
Negative75.0%

Bugs and requests

Function Health

Reported bugs

2 issues
  • App sometimes redirects back to the home screen when trying to view results
  • Occasional typos and formatting issues in the app

Requested features

3 requests
  • More customization options in the app settings
  • Ability to print or export test results and recommendations
  • Specific supplement recommendations rather than broad suggestions

BIDSleep

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Function Health

No in-app purchases

None

BIDSleep

No in-app purchases

Questions

Is Function Health free?
Function Health is free to download, with no in-app purchases.
Is BIDSleep free?
BIDSleep is free to download, with no in-app purchases.
Which has better reviews, Function Health or BIDSleep?
Function Health is rated higher. Function Health averages 4.9 out of 5 from 25K ratings, while BIDSleep averages 2.0 from 4 ratings.
Do Function Health or BIDSleep have ads?
Neither Function Health nor BIDSleep shows ads.

Other comparisons