The best apps to track muscle gain
Muscle comes on slowly and hides behind pump and lighting. These apps make it visible, and help you tell muscle from fat.
Short answer
The best way to track muscle gain is two apps: a workout log for strength (Hevy, free) and ProgressLens for matched photos plus arm, chest, shoulder and waist measurements, with an AI report that tells you whether a bulk is adding muscle or mostly fat. GainFrame scores muscle groups from photos on iPhone.
Disclosure: we make ProgressLens. Details about other apps come from their own store listings and websites as of November 2026; prices and features change, so check the listing before you pay. We name each app’s weaknesses and our own.
Quick comparison
| App | Platforms | What it tracks | Price model |
|---|---|---|---|
| ProgressLens | iPhone, Android | Arms, chest, shoulders, thighs + matched photos; lean bulk rate | $39.99/year |
| GainFrame | iPhone | Muscle-group scores, FFMI from photos | Subscription |
| Hevy | iPhone, Android | Strength progress, volume; photos | Free + Pro |
| MacroFactor | iPhone, Android | Calorie surplus; photos and measurements | Subscription |
| ZOZOFIT | iPhone, some Android | 3D circumferences | Free + Premium |
| Progress Body Tracker | iPhone | Custom tape measurements | Subscription for photos |
The apps
1. ProgressLens
- iPhone, iPad, Android
- AI Progress Report
- Free download, Pro in-app
- 11 languages
- No account
Best for: seeing slow muscle gain and keeping a bulk lean.
Muscle gain is slow: a beginner might add half a kilo of muscle a month, which no mirror can see week to week. ProgressLens lines up photos with a ghost overlay and tracks arms, chest, shoulders and thighs against your waist, so you can tell muscle from fat. The Progress Report flags a bulk that’s adding mostly fat and gives a weekly gain rate.
Good
- AI Analyze: body-fat range, what changed, fat vs muscle, cut or bulk verdict
- Reads photos and tape measurements together, so estimates stay consistent
- Same app and AI on iPhone and Android, in 11 languages
- No account; photos stay on your phone, analyzed photos aren’t stored or used for training
- Ghost overlay of your last photo, six measurements with charts
Watch out
- No calorie, workout or dose tracking
- No video timelapse export (use our free web tool)
- No Apple Health or Health Connect sync
- No app-specific passcode (use your phone’s lock)
2. GainFrame
- iPhone, iPad (no Android)
- Subscription (listing shows weekly, monthly and $39.99–49.99 yearly tiers)
Best for: iPhone users who want muscle-group scores.
An AI-first physique app for iPhone with body fat estimates, 12 muscle-group scores and a chat coach. AI body fat, FFMI, physique and muscle-group scores from photos, AI coach.
Good
- 12 muscle-group scores
- FFMI
Watch out
- iPhone only
- Scores swing with pump and light
3. Hevy
- iPhone, Android
- Workout tracker
- Free + Pro subscription
Best for: strength, the most direct sign of muscle gain.
A workout log first. Free users can add one progress photo a day and track bodyweight and waist; Pro adds body fat and more circumferences (per its help centre).
Good
- Free
- Excellent workout log
Watch out
- Photos are basic
4. MacroFactor
- iPhone, Android
- Nutrition coach
- Subscription
Best for: keeping a surplus small and steady.
A nutrition app with an adaptive calorie coach. Since 2023 it has a Body Metrics section with front, side and back progress photos and a before-and-after gallery (per its help centre).
Good
- Adaptive calories
Watch out
- No photo analysis
5. ZOZOFIT
- iPhone, some Android phones
- Free plan; Premium monthly, yearly or lifetime
Best for: 3D circumference measurements.
A 3D body scanner focused on circumference measurements rather than photos. 3D body scan with 16 measurements, posture and GLP-1 logs.
Good
- 16 measurements
Watch out
- Limited Android devices
6. Progress Body Tracker
- iPhone
- Measurement-first
- Subscription for photos
Best for: people who like many custom tape sites.
A long-running tracker for weight and many custom tape measurements with Apple Health sync; progress photos are part of Pro (per its listing).
Good
- Custom measurements
Watch out
- iPhone only
- Photos cost extra
Which should you pick?
- Muscle vs fat on a bulk: ProgressLens.
- Strength: Hevy.
- Calories: MacroFactor.
- Muscle scores on iPhone: GainFrame.
FAQ
Frequently asked questions
What is the best app to track muscle gain?
Use two: a workout log for strength (Hevy is free) and ProgressLens for matched photos plus arm, chest and shoulder measurements with an AI read of fat vs muscle.
How can I tell if I’m gaining muscle or fat?
If your arms, chest and shoulders grow faster than your waist and your lifts go up, it’s mostly muscle. If your waist grows fastest, slow the surplus. Read how to track muscle gain.
How much muscle can I gain in a month?
Roughly 0.5–1 kg (1–2 lb) a month in your first year, less after. See how much muscle you can gain.
Do progress photos show muscle gain?
Over 8–12 weeks, yes, if they’re taken the same way every time. Week to week, pump and lighting hide it, which is why measurements matter.
Sources
- App Store and Google Play listings for each app, accessed November 2026
- ProgressLens, What lifters ask about body fat, November 2026