Goniometer: Joint Angle & ROM

Measure joint range of motion with your phone. Goniometer turns your device's motion sensor into a digital goniometer, so you can track knee, elbow, shoulder, hip, ankle, wrist and neck mobility anywhere — at the clinic, the gym, or at home.

Pick the joint and motion you're testing, lay the phone flat along the limb, tap Tare to zero at the neutral position, then move through the motion and capture the ends. The app shows your range of motion in degrees and as a percentage of the normal range for that joint.

WHAT YOU GET

• Digital goniometer — live joint angle from the phone's accelerometer.
• Tare to neutral — zero at the limb's anatomical-zero so you read true movement, not gravity.
• Capture min and max — record both ends of the motion to compute ROM automatically.
• Measured vs normal — see your ROM next to typical adult values, with a percent-of-normal readout.
• Many joints — knee, elbow, shoulder, hip, ankle, wrist flexion and extension, and neck.
• Normal ROM reference — a built-in table of typical adult active range-of-motion values.
• Step-by-step guide — clear instructions and accuracy tips for repeatable measurements.

WHO IT'S FOR

Physical therapy and rehab patients tracking recovery, PTs and trainers, yoga and mobility enthusiasts, and anyone curious about their flexibility.

A NOTE ON ACCURACY

Readings depend on your phone's sensor and how it's aligned to the limb. This app is a measurement aid for fitness and education — it is not a medical device and does not diagnose. Consult a qualified clinician for assessment.