Measure your flexibility. Watch it change.
Movement Lab uses your iPhone camera to measure your range of motion in degrees, on your left side and your right. You’ll see how you compare with people your age, and if you test again every few weeks, whether your mobility work is paying off.
Start free on iPhone See how it works
Testing is free. Your video stays on your phone.
Example result for an overhead squat, measured facing the camera and then side on. Facing the camera, knee tracking was 1.03 and the knees caved in during the hold. Side on, knee bend was 131 degrees and trunk lean 36 degrees, and the arms fell forward during the hold. Retested every four weeks, knee bend went from 108 to 131 degrees in twelve weeks.
Why
Most mobility apps can’t tell you if you’re getting more flexible.
You can follow a program for six months and still not know if your hips move any further than when you started. The apps give you videos and a streak counter, but they don’t measure anything.
Movement Lab does the measuring. Keep doing whatever program you like, test every few weeks, and you’ll have a record of how far you actually move.
How it compares
Other tools either don’t measure your range, don’t keep a history, or aren’t sold to individuals.
| Stretching apps | Form-check apps | Clinic tools | Movement Lab | |
|---|---|---|---|---|
| Measures your range | No | One rep at a time | Yes | Yes, in degrees |
| Keeps the record over time | Workouts done, not range gained | No | Yes | Yes |
| Sold to individuals | Yes | Yes | Sold to clinics | Yes, free to test |
Who it’s for
Anyone who wants a real number for how well they move, whether they train six days a week or are just starting again.
Hybrid athletes
If you run and lift in the same week, keep an eye on your hip and ankle range as your training load changes.
Casual athletes
Weekend runs, tennis, pickup basketball. Find out how mobile you are and keep track of it without signing up for a program.
Climbers and boulderers
High steps, lock-offs and heel hooks depend on hip, shoulder and ankle range. Most climbers are tighter on one side, and the tests show by how much.
Lifters
If you can’t squat to depth or hold a bar overhead, the tests show whether it’s your ankles, hips or shoulders. Then you can track that one number.
Martial artists
Guard retention and high kicks depend on hip rotation and split range. You can measure both.
Skiers
Ankle and hip range matter on the mountain. Test in the fall, work on it, and test again before your first day out.
Getting back into it
If you’re returning to exercise after years away, test where you are now and see how your range changes as you get moving again.
People who sit all day
Long days at a desk tend to show up in your hips and shoulders. The tests show where you’re tight, and retesting shows whether your stretching breaks help.
How
Each test takes about three minutes.
- Prop your phone up. Each test has a diagram showing where to put the phone and which way to face.
- Move as far as you can and hold it. The app measures the hold, not a single frame.
- Read your result. You get your joint angles, the difference between sides, and any compensations it spotted. You can share the result card.
- Test again when it’s due. The app reminds you, and each session adds to your history.
What the result shows
Joint angles
How far each joint moves at the end of your range, in degrees.
Left vs. right
Most people have a tighter side without knowing it. Every two-sided test shows the difference.
How you compare
Your home screen shows a percentile next to each test you’ve done, like the 68th percentile for men 35 to 44.
Compensations
Bending your knees in a fold or lifting a hip in a rotation makes your range look bigger than it is. The app flags it.
History
Each test has a retest window of two to four weeks. After a few months of results you can see if your training is working.
The 16 tests
- Overhead squat
- Standing forward fold
- Seated forward fold
- Side split
- Front split
- Back bridge
- Thrower’s stretch
- Behind-the-back hand touch
- Back-to-wall shoulder flexion
- Seated hip rotation
- Seated thoracic rotation
- Ankle knee-to-wall
- Straight leg raise
- Thomas test
- High step
- Pancake
Privacy and accuracy
Your video never leaves your phone. Pose detection runs on your iPhone with Apple Vision. Frames are never uploaded. We only store the joint angles.
Each test tells you what it can’t measure. For example, the ankle test reports your shin angle instead of the distance from your toe to the wall, because the camera has no foot joint to measure from.
What each test measures and what it can’t
- Overhead squat
- Depth, trunk lean and knee tracking, from the front and the side.
- Standing forward fold
- Measures wrist-to-ankle distance, not fingertip-to-floor.
- Seated forward fold
- A floor pose. Vision is trained on upright bodies, so tracking is less reliable than standing tests.
- Side split
- Cannot see hip or foot rotation, which is often what actually limits this.
- Front split
- The rear leg is partly hidden at end range. Pelvis rotation is inferred from apparent hip width.
- Back bridge
- An inverted pose. Tracking is unreliable here; treat the numbers as indicative.
- Thrower’s stretch
- The reach distance is only meaningful in 3D. Without it, only the projected gap is shown.
- Behind-the-back hand touch
- Measures wrist separation, not fingertip separation. Track the trend, not the absolute number.
- Back-to-wall shoulder flexion
- Cannot see the lumbar directly; trunk lean is the proxy for losing wall contact.
- Seated hip rotation
- Lifting the hip fakes range. Hip level is tracked so that cheat shows up.
- Seated thoracic rotation
- Needs the 3D pose to resolve. If it does not, only a coarse proxy is shown.
- Ankle knee-to-wall
- Reports shin angle from vertical, not toe-to-wall distance. Vision has no foot or toe joint.
Pricing
Testing is free and your latest result for each movement stays visible. You pay if you want your full history and trends.
Free
$0
Every test, and your latest result for each movement.
Annual
$59.99/year
Full history and trends for a year. Renews yearly until you cancel.
If you cancel, nothing is deleted. Your old sessions stay listed and unlock again if you subscribe again. Prices are in US dollars.
Questions
How is this different from a stretching app?
Stretching apps give you routines to follow. Movement Lab measures your range of motion and keeps track of it, so you can see if a routine is working. You can use it alongside whatever you already do.
How accurate is it?
It uses a single camera and the 19 body joints Apple Vision tracks. That’s enough for joint angles, reach distances and left/right differences. It isn’t enough for spinal flexion, foot position or anything behind your body. Each test lists its limits in the app.
How does the percentile work?
Your latest result for each test is compared with people of the same sex and age range, which you can add in Settings. Leave them out and you’re compared with everyone. To start with, comparisons come from published range-of-motion studies, and the app shows which study. Once a group has at least 100 Movement Lab users, it uses their results instead. Tests without good published data don’t show a percentile until that group fills up.
Is my video uploaded?
No. Pose detection runs on your iPhone and frames are never uploaded. Only the derived joint angles are stored.
What do I need?
An iPhone, something to lean it against, and six to ten feet of space. No wearables or other equipment.
Is this a medical device?
No. Movement Lab is a measuring tool for training. It doesn’t diagnose, treat or assess injury risk. If something hurts, see a clinician.
How often should I retest?
Every 14 to 28 days, depending on the test. The app reminds you when one is due.
What happens if I cancel?
Nothing is deleted. Your older results stay listed with the movement and date, and the scores unlock again if you subscribe again.
Take your first test for free
It takes about three minutes. All you need is your iPhone.