Wrist Function · iPhone App
Jointy uses your iPhone's motion sensors to score wrist rotation, control, flexibility, and steadiness — independently for both wrists — and shows you how your movement changes over time.
Free to try · iPhone only · No account required
The Problem
You might notice stiffness, asymmetry between sides, a change in grip, or wrists that just feel "off" — but without any way to measure the movement, you have no baseline, no reference, and no way to know if things are getting better or worse.
Jointy gives you a structured, repeatable way to check four key areas of wrist function and see how they change over days and weeks — using only your iPhone.
Without a starting measurement, you can't tell if your wrist function is improving, declining, or staying the same.
Left and right wrists often perform differently — but without measurement, most people can't detect or track that gap.
Wrist stiffness and range of motion changes gradually. Without regular measurement, those changes are invisible.
How It Works
Jointy's full bilateral wrist assessment takes less than two minutes and requires only your iPhone.
Sit comfortably with your arm resting at 90°, elbow tucked. Hold the phone flat in your palm, screen up. One wrist at a time.
Each measurement is 10 seconds. On-screen instructions show you exactly what to do for each test.
Jointy shows your left wrist score, right wrist score, overall score, and balance between sides. Every session is logged so you can see how your scores change over time.
The Four Measurements
Each measurement targets a distinct aspect of wrist and forearm function. All four are scored 0–100 and contribute equally to your overall score.
Turn your wrist like turning a key — rotating your forearm back and forth with your elbow tucked. Jointy's gyroscope tracks the full arc of rotation in both directions and measures how smoothly you move through it. Forearm rotation is one of the most-used movements in daily life, from opening jars to typing.
Draw slow, steady circles with your wrist. Jointy tracks how consistently you maintain speed and how smoothly you move through the full circle. Control is what separates range of motion from functional movement — you can have good range but poor control. Control also responds quickly to focused practice.
Bend your wrist toward you (flexion), then extend it past flat (extension). Jointy measures both peak flexion and peak extension angles using your phone's motion sensors. A healthy wrist typically reaches around 60° of flexion and 35° of extension. Most people lose extension range first — especially desk workers.
Hold your wrist perfectly still for 10 seconds. Jointy's accelerometer measures how much your wrist moves — capturing both average tremor (RMS) and any sudden spikes. Stability is the foundation of every grip, lift, and fine motor task. It's often the most overlooked measurement, and the one most affected by fatigue and overuse.
Your Results
After each assessment, Jointy shows a full breakdown of your wrist function — not just a single number, but a complete picture of how both wrists are performing and where the gap between them is.
Daily Check-In & Tracking
A single session gives you a snapshot. What makes Jointy useful is the trend — seeing whether your scores are improving, stable, or declining over days and weeks.
Every session is logged with timestamp, left/right scores, and per-subscore breakdown.
Run a full bilateral assessment in under two minutes to keep your trend data fresh.
After a week of consistent check-ins, Jointy generates a weekly summary showing your average scores, per-subscore trends, and balance shifts.
Jointy identifies your weakest subscore and suggests short guided wrist reset routines to target that area.
Who It's For
Jointy is useful for anyone who wants a clearer way to monitor wrist movement, stiffness, balance, and progress over time.
Hours of typing and mousing hold wrists in a static position. Jointy tracks the stiffness and range-of-motion changes that build up over time.
Extended gaming sessions put wrists under repetitive strain. Use Jointy to monitor rotation, control, and stability — and track whether changes are accumulating.
Pianists, guitarists, and other instrumentalists depend on precise wrist function. Jointy gives a clear measurement of what's happening across both wrists.
Wrist loading in lifting, CrossFit, and calisthenics changes wrist function over time. Track your baseline and spot asymmetry before it becomes an issue.
Construction, plumbing, mechanics — high-demand hand work puts cumulative load on both wrists. Jointy helps you monitor that load over time.
For anyone who notices stiffness, reduced range, or imbalance between sides and wants a structured, data-driven way to see if things are changing.
Designed With Care
Jointy is a measurement tool. We're clear about what it is, what it isn't, and how it handles your data.
All wrist motion data and scores are stored locally on your iPhone. Jointy does not transmit, sell, or share your sensor data. Confirmed in the app's privacy manifest: no data is collected or sent off-device.
Jointy measures wrist movement patterns. It does not diagnose medical conditions, detect injuries, or replace professional medical evaluation. Scores are for self-tracking only.
You don't need to create an account or sign in to use Jointy. Download the app and start measuring immediately. No email, no password, no tracking.
Safety note: Jointy measurements involve wrist movement. Stop immediately if any movement causes sharp pain, and do not push past your comfortable range. Jointy is not a substitute for medical advice. If you have wrist pain, numbness, tingling, or a recent injury, consult a qualified healthcare professional — physiotherapist, sports medicine doctor, or orthopaedic specialist — before using this app. This app is not intended to diagnose, treat, cure, or prevent any condition.
FAQ
Straightforward answers about how Jointy works.
Get Started
Free to try. No wearable. No account. Just your iPhone and two minutes.
Download on the App StoreiPhone · iOS 18 or later · No account required
