Side by side.
| Feature | Withings | Renpho Health | Hevy | Phaze | Bodymapp | Pip Body Scan |
|---|---|---|---|---|---|---|
| What it tracks | Weight, fat mass and muscle mass from a compatible Withings scale; six-zone estimates on supported models | Muscle mass, skeletal muscle, body fat and more, from a Renpho scale | Sets, reps and weights for every lift, with strength graphs and records | An AI photo estimate of body fat and muscle (beta), and clinic scan results you import | Skeletal muscle mass and up to 20 metrics | Body shape in 3D, waist, a body-fat range and a fat-free mass range |
| How | A Withings body-composition scale | Bioelectrical impedance as you stand on the scale | You log each workout | Photos sent to a third-party AI, after you agree | The Face ID depth sensor while you turn | Four photos (front, both sides, back) on the front camera, hands-free |
| Is the muscle figure a measurement? | An estimate from the scale | An estimate from electrical resistance | No figure. It tracks your training, not your body | An estimate, which Phaze says has a 3 to 5% margin | An estimate from body shape | No muscle figure. Fat-free mass isn’t muscle |
| Extra kit | A Withings scale | A Renpho scale | None | None | A Face ID iPhone (iPhone X or later) | None |
| GLP-1 tools | Not stated in its listing | Not stated on their site | Not stated on their site | Dose log, site rotation and side effects | Not stated on their site | Shot log, side effects and reminders |
| Phones | iPhone, iPad and Android | iPhone and Android | iPhone and Android | iPhone, Apple Watch and Android | Face ID iPhones (iPhone X or later). No Android phone app | iPhone only (iOS 17 or later) |
| What you need | Free app. Scales sold separately. Withings+ is optional | Free app. Scales sold separately | Free, with no ads. Hevy Pro is optional | Body composition needs Phaze Pro | A limited free plan. Premium for unlimited scans | No free tier or trial. Your first scan is free to take; join to see your results |
| US App Store rating | 4.6 (368,621) | 4.7 (9,001) | 4.9 (100,002) | 4.6 (43) | 4.3 (7) | Not on the App Store yet |
Withings’ current scale page and both app listings were read on 26 October 2026. Six-zone composition requires a compatible model; it is not a feature of every Withings scale. The five other apps are free to download on the US App Store. Pip Body Scan is coming soon to the App Store, for iPhone, and needs a membership to see your results.
How we ranked
We grouped apps by the kind of record they provide: scale-based composition estimates, then a strength-training log, then phone-based composition estimates. Within each group they appear in order of US ratings, so Withings precedes Renpho. Rating counts break a tie in this table; they do not show which estimate is more accurate. Choose the app compatible with a scale you already own. Pip Body Scan is last because it has no muscle figure. We have not independently tested the apps or rival hardware.
The clinic option: a DEXA scan
A DEXA (dual-energy X-ray absorptiometry) scan sorts your body into fat, bone and lean mass. It’s how GLP-1 trials measure body composition: in a SURMOUNT-1 substudy, about a quarter of the weight lost on tirzepatide was lean mass. Lean mass includes muscle, but also organs and water, so even DEXA doesn’t isolate muscle.
No phone app replaces it. If knowing your muscle matters for your care, ask your doctor whether a body-composition scan makes sense for you.
Smart scales: an estimate at every weigh-in
Renpho and Withings scales estimate fat and muscle from how your body conducts a small electrical signal. Renpho Health sends weight, body fat, BMI and lean body mass to Apple Health. Withings’ September 2026 update (version 26.40) put weight, fat mass and muscle mass together in one Body Composition section, with a status after every weigh-in.
The readings move with water, food and time of day, so the trend over weeks matters more than any one number. Renpho says people who are pregnant or have a pacemaker or metal implants should use its scales for weight only.
Strength logs: track what you can control
Guidance on GLP-1 treatment recommends strength training, and a strength log tells you exactly what you did. Hevy logs every set, rep and weight, and graphs your progress on each exercise. Strong does the same, and its free version saves unlimited workouts with up to three custom routines. Lifts that hold steady while the scale falls are a practical signal you can see for yourself.
What Pip Body Scan can add
Pip Body Scan doesn’t measure muscle, and its fat-free mass range isn’t a muscle figure. What it can add is context: a weekly 3D body that shows where your shape is changing, your waist, a fat-free mass range, and a workout card that counts your strength days and cardio minutes.
Pip reads workouts from Apple Health, so if you turn on Hevy’s Apple Health export, sessions you log in Hevy can show up in Pip. If muscle is your main question, use a scale or a clinic scan alongside it, or instead of it.
Which one fits you?
- Withings
- You already use Withings devices, or want weight, fat and muscle together in one view.
- Renpho Health
- You use a compatible Renpho scale and want its composition estimates alongside your weight, on iPhone or Android.
- Hevy
- You want to track the training itself, set by set, for free.
- Phaze
- You want a GLP-1 tracker that adds a photo-based muscle estimate and keeps your clinic scan results.
- Bodymapp
- You have a Face ID iPhone and want a skeletal muscle estimate without buying a scale.
- Pip Body Scan
- You want to see your shape change week to week alongside your shots, and you’ll use something else for muscle.
Questions people ask.
Can a phone app measure muscle?
Not directly. Smart scales estimate muscle from electrical resistance, and photo apps estimate it from your shape. A DEXA scan measures lean mass, which includes muscle along with organs and water.
Does Pip Body Scan track muscle?
No. It shows a fat-free mass range, an AI estimate that isn’t muscle. It can count your strength sessions from what you log or from Apple Health.
Where these facts come from.
Rival websites and App Store listings read on 26 October 2026. Ratings are from the US App Store, using Apple’s public lookup, on the date shown for each app. Features are what the developers advertise, not results from hands-on testing or an independent security or clinical assessment. Free and paid access can change; check the app before choosing.
- Pip Body Scan Pip Body Scan facts sheet, checked against the current iPhone build on 25 October 2026. How Pip estimates work
- Withings App Store listing and version history (version 26.40 of 28 September 2026 added the Body Composition section; the current version on 26 October 2026 was 26.42, of 12 October); Google Play listing and Withings’ current scale comparison page, read 26 October 2026. Website · App Store · Free download. Rating checked 26 October 2026.
- Renpho Health renpho.com home page, app page, smart scale range and the Elis 1 and MorphoScan scale pages; App Store listing. No in-app purchases are listed. Website · App Store · Free download. Rating checked 26 October 2026.
- Hevy hevyapp.com home page; App Store listing. Website · App Store · Free download. Rating checked 26 October 2026.
- Phaze phaze.fit home page, pricing table and FAQ, plus its injection tracker, body tracking and body composition pages; App Store listing. Website · App Store · Free download. Rating checked 26 October 2026.
- Bodymapp bodymapp.co home page and FAQ; App Store listing. Its FAQ also names iPad Pro, but its App Store listing says it’s for iPhone only, on Face ID models from iPhone X. Website · App Store · Free download. Rating checked 25 October 2026.
- Strong App Store listing. Website · App Store · Free download. Rating checked 26 October 2026.
- Withings smart-scale comparison. Current models and which support segmental fat and muscle estimates. No independent accuracy comparison was performed. Read it. Checked 26 October 2026.
- Withings on Google Play. The Android version of the Withings app. Read it. Checked 26 October 2026.
- SURMOUNT-1 body composition substudy. Look M et al. Diabetes Obes Metab 2025;27:2720-2729. DEXA results for 160 trial participants over 72 weeks. Read it. Checked 26 October 2026.
Pip Body Scan is a personal progress-record tool. It does not provide medical advice, diagnose conditions or recommend treatment or doses. Body-fat and waist figures are AI estimates, not medical measurements. Speak to a qualified healthcare professional about medical concerns or changes to a treatment plan. Other app names are trademarks of their owners and are used here only to compare.