Goniometer: Range of Motion

Turn your iPhone into a goniometer — 47 movements, neck to fingertips, with guided placement. Try Pro free for 7 days: no card, no auto-charge, no subscription.

Measure joint range of motion with the device already in your pocket. Goniometer turns the iPhone's motion sensor into a clinical-style goniometer: place the phone against the limb, read the live angle, and lock it when steady.

Built for occupational and physical therapists, hand therapists (CHTs), chiropractors, physicians, nurses, athletic trainers, ATPs, and students — and used by patients tracking their own recovery at home. Reviewed against standard supine measurement technique. Smartphone inclinometer measurement has been shown valid and reliable in peer-reviewed research (Keogh et al., systematic review, PLOS ONE, 2019).

MEASURE IN SECONDS • Live, gravity-referenced angle with a large readable display • Flat and upright starting positions read 0° automatically — no calibration • Set Zero baseline override for patients who can't reach the standard start position • Stability indicator: lock only when the reading is steady • Optional spoken angle so both hands stay on the patient

ANIMATED PLACEMENT GUIDES Every movement has a step-by-step animated guide with a clear anatomical diagram: patient position, exactly where the iPhone lies, and what the motion looks like from start to end range.

47 MOVEMENTS — NECK, UPPER AND LOWER EXTREMITY, AND EVERY FINGER Cervical spine flexion, extension, lateral flexion, and rotation · shoulder flexion, abduction, and external rotation · elbow flexion and extension · wrist flexion, extension, and radial/ulnar deviation · hip flexion and external rotation · knee flexion and extension · ankle dorsiflexion and plantarflexion.

HAND & FINGER ROM Measure every finger and thumb joint — MCP, PIP, and DIP (and thumb MCP/IP), flexion and extension — with a guided two-placement technique. Patient Profiles compute Total Active Motion (TAM) per digit automatically — a standout for hand therapists (CHTs).

QUICK ANGLE & LEVEL — MEASURE ANY ANGLE Measure any angle with Quick Angle — wheelchair frames, splints and orthoses, ramps, seating — and check that footplates, seats, and trays sit even with the built-in Level. Both are free.

NORMAL ROM REFERENCE A free, searchable reference of normal range values for every movement, linked to each placement guide.

PATIENT PROFILES — YOUR FIRST ONE IS FREE Create a profile with a de-identified label, a movement checklist, and left/right sides, then record a reading for each movement. Tag readings active or passive (AROM/PROM) and add, correct, or backdate any reading. Your first profile is free, watermarked PDF and CSV export is free, and a deletable example patient lets you explore trend charts, summaries, and reports instantly.

PRIVATE BY DESIGN — NO DATA COLLECTED Fully offline: no accounts, no servers, no analytics, no tracking — the App Store privacy label reads "Data Not Collected." Profiles use de-identified labels, are encrypted on this device, stay out of cloud backups, and leave your iPhone only when you export a report yourself. Designed to support HIPAA-compliant documentation, with a free Face ID lock and permanent deletes.

TRY PRO FREE FOR 7 DAYS Use every Pro feature for a week — no credit card, no automatic charge, nothing to cancel. The trial simply ends and everything stays saved.

GONIOMETER PRO — ONE-TIME PURCHASE, NO SUBSCRIPTION • Unlimited patient profiles • Progress history: every reading kept and graphed across visits • Goal tracking: set a target angle per movement, shown on every chart and report • Total Active Motion (TAM) per finger, computed automatically • Side-to-side comparison: each side as a percentage of the contralateral limb • Watermark-free PDF and CSV reports with the clinical summary and progress charts • Clinic letterhead: your clinic's name and logo on every report • Hands-free auto-lock: the angle captures itself once the limb is held steady

Available in English and Spanish.

Goniometer is an educational and reference tool. It is not a medical device and is not intended for diagnosis or treatment decisions.